GMAB 6-K
Genmab A/S (GMAB)
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 6-K
REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16
OF THE SECURITIES EXCHANGE ACT OF 1934
FOR THE MONTH OF MARCH 2025
COMMISSION FILE NUMBER 001-38976
Genmab A/S
(Exact name of Registrant as specified in its charter)
Carl Jacobsens Vej 30
2500 Valby
Denmark
+45 70 20 27 28
(Address of principal executive offices)
Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.
Form 20-F ⌧ Form 40-F ◻
This report on Form 6-K shall be deemed to be incorporated by reference in Genmab A/S’s registration statements on Form S-8 (File No. 333-232693, 333-253519, 333-262970, 333-277273 and 333-284876) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.
SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.
| nthony | | |
|---|---|---|
| | GENMAB A/S | |
| | | |
| | BY: | /s/ Anthony Pagano |
| | | Name: Anthony Pagano |
| | | Title: Executive Vice President & Chief Financial Officer |
DATE: MARCH 31, 2025
EXHIBIT INDEX
| O | |
|---|---|
| Exhibit | Description of Exhibit |
| | |
| 99.1 | Company Announcement Dated March 31, 2025: Transactions in Connection with Share Buy-back Program |
| 99.1(a) | Appendix: Share Buy-Back Program Transactions March 26 to 28, 2025 |
Exhibit 99.1

Transactions in connection with share buy-back program
Company Announcement
COPENHAGEN, Denmark; March 31, 2025 – Genmab A/S (Nasdaq: GMAB). On March 25, 2025, Genmab announced the initiation of a share buy-back program to repurchase up to 2.2 million shares to reduce capital and to honor our commitments under the Restricted Stock Unit program. The share buy-back program is expected to be completed no later than July 10, 2025.
The following transactions were executed under the program from March 26 to March 28, 2025:
| Trading Platform | No. of shares | Average price (DKK) | Total value (DKK) | ||
| March 26, 2025 | XCSE | 45,467 | 1,357.43 | | |
| | BCXE | 21,311 | 1,357.41 | | |
| | AQEU | 4,148 | 1,359.16 | | |
| | TQEX | 4,174 | 1,356.43 | | |
| | Total | 75,100 | 1,357.47 | 101,945,764.19 | |
| March 27, 2025 | XCSE | 48,249 | 1,380.52 | | |
| BCXE | 23,000 | 1,380.11 | | ||
| | AQEU | 4,357 | 1,382.59 | | |
| | TQEX | 4,472 | 1,378.49 | | |
| | Total | 80,078 | 1,380.40 | 110,539,671.20 | |
| March 28, 2025 | XCSE | 46,924 | 1,371.40 | | |
| | BCXE | 23,961 | 1,371.22 | | |
| | AQEU | 2,693 | 1,371.96 | | |
| | TQEX | 4,800 | 1,371.78 | | |
| | Total | 78,378 | 1,371.39 | 107,486,507.58 | |
| Total | | 233,556 | | 319,971,942.97 |
Details of each transaction are included as an appendix to this announcement.
Following these transactions, Genmab holds 2,771,544 shares as treasury shares, corresponding to 4.19% of the total share capital and voting rights.
The share buy-back program is undertaken in accordance with Regulation (EU) No. 596/2014 (‘MAR’) and the Commission Delegated Regulation (EU) 2016/1052, also referred to as the “Safe Harbour Regulation.” Further details on the terms of the share buy-back program can be found in our company announcement no. 14 dated March 25, 2025.
About Genmab
Genmab is an international biotechnology company with a core purpose of guiding its unstoppable team to strive toward improving the lives of patients with innovative and differentiated antibody therapeutics. For more than 25 years, its passionate, innovative and collaborative team has invented next-generation antibody technology platforms and leveraged translational, quantitative and data sciences, resulting in a proprietary pipeline including bispecific T-cell engagers, antibody-drug conjugates, next-generation immune checkpoint modulators and effector function-enhanced antibodies. By 2030, Genmab’s vision is to transform the lives of people with cancer and other serious diseases with knock-your-socks-off (KYSO) antibody medicines^®^.
| | | |
|---|---|---|
| Genmab A/S | Tel: +45 7020 2728 | Company Announcement no. 15 |
| Carl Jacobsens Vej 30 | Fax: +45 7020 2729 | Page 1/2 |
| 2500 Valby, Denmark | www.genmab.com | CVR no. 2102 3884 |
| | | LEI Code 529900MTJPDPE4MHJ122 |

Transactions in connection with share buy-back program
Established in 1999, Genmab is headquartered in Copenhagen, Denmark, with international presence across North America, Europe and Asia Pacific. For more information, please visit Genmab.com and follow us on LinkedIn and X.
Contact:
Marisol Peron, Senior Vice President, Global Communications & Corporate Affairs
T: +1 609 524 0065; E: [email protected]
Andrew Carlsen, Vice President, Head of Investor Relations
T: +45 3377 9558; E: [email protected]
This Company Announcement contains forward looking statements. The words “believe,” “expect,” “anticipate,” “intend” and “plan” and similar expressions identify forward looking statements. Actual results or performance may differ materially from any future results or performance expressed or implied by such statements. The important factors that could cause our actual results or performance to differ materially include, among others, risks associated with pre-clinical and clinical development of products, uncertainties related to the outcome and conduct of clinical trials including unforeseen safety issues, uncertainties related to product manufacturing, the lack of market acceptance of our products, our inability to manage growth, the competitive environment in relation to our business area and markets, our inability to attract and retain suitably qualified personnel, the unenforceability or lack of protection of our patents and proprietary rights, our relationships with affiliated entities, changes and developments in technology which may render our products or technologies obsolete, and other factors. For a further discussion of these risks, please refer to the risk management sections in Genmab’s most recent financial reports, which are available on www.genmab.com and the risk factors included in Genmab’s most recent Annual Report on Form 20-F and other filings with the U.S. Securities and Exchange Commission (SEC), which are available at www.sec.gov. Genmab does not undertake any obligation to update or revise forward looking statements in this Company Announcement nor to confirm such statements to reflect subsequent events or circumstances after the date made or in relation to actual results, unless required by law.
Genmab A/S and/or its subsidiaries own the following trademarks: Genmab^®^; the Y-shaped Genmab logo^®^; Genmab in combination with the Y-shaped Genmab logo^®^; HuMax^®^; DuoBody^®^; HexaBody^®^; DuoHexaBody^®^, HexElect^®^ and KYSO^®^.
| | | |
|---|---|---|
| Genmab A/S | Tel: +45 7020 2728 | Company Announcement no. 15 |
| Carl Jacobsens Vej 30 | Fax: +45 7020 2729 | Page 2/2 |
| 2500 Valby, Denmark | www.genmab.com | CVR no. 2102 3884 |
| | | LEI Code 529900MTJPDPE4MHJ122 |
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| Issuer | Date | Time CET | Quantity | Price (DKK) | Venue |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 9:30:18 AM | 70 | 1337.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:30:42 AM | 42 | 1338.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:30:42 AM | 67 | 1338.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 56 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 68 | 1339.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 1 | 1339.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 4 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 24 | 1339.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 39 | 1338.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 63 | 1339.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 68 | 1338.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 64 | 1338.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 9:32:04 AM | 71 | 1339.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 9:34:10 AM | 30 | 1339.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:36:02 AM | 18 | 1340.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:36:02 AM | 37 | 1340.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:36:02 AM | 32 | 1340.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 9:36:04 AM | 72 | 1340.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:36:04 AM | 7 | 1340.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:36:04 AM | 16 | 1340.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:36:06 AM | 26 | 1339.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:36:06 AM | 12 | 1339.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:39:00 AM | 23 | 1339.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 9:39:01 AM | 23 | 1339.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:39:11 AM | 15 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:39:19 AM | 54 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:39:32 AM | 22 | 1338.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:39:32 AM | 3 | 1338.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:39:33 AM | 75 | 1338.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:39:33 AM | 53 | 1338.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:40:16 AM | 39 | 1337.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:40:16 AM | 3 | 1337.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:41:21 AM | 72 | 1337.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:41:21 AM | 34 | 1337.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:41:24 AM | 33 | 1336.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:41:24 AM | 14 | 1336.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:41:24 AM | 23 | 1336.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:42:39 AM | 73 | 1335.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:42:39 AM | 48 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:42:39 AM | 27 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:42:39 AM | 44 | 1335.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:43:04 AM | 71 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:43:04 AM | 64 | 1333.50 | CEUX |
1
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 9:43:27 AM | 71 | 1332.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 9:43:27 AM | 49 | 1332.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:43:29 AM | 1 | 1331.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:44:14 AM | 8 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:44:14 AM | 24 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:45:04 AM | 71 | 1334.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:46:05 AM | 73 | 1334.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:47:01 AM | 23 | 1334.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:47:12 AM | 12 | 1334.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:47:12 AM | 11 | 1334.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:47:28 AM | 20 | 1334.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:48:01 AM | 23 | 1335.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:48:01 AM | 4 | 1335.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:48:01 AM | 74 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:48:26 AM | 2 | 1334.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:48:50 AM | 12 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:48:50 AM | 58 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:49:03 AM | 73 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:49:27 AM | 29 | 1334.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:49:28 AM | 52 | 1334.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:49:28 AM | 23 | 1334.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:50:01 AM | 1 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:50:01 AM | 69 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:50:02 AM | 18 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:50:02 AM | 42 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:50:02 AM | 21 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:50:02 AM | 4 | 1332.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:50:02 AM | 42 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:50:02 AM | 27 | 1333.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:51:32 AM | 42 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:51:32 AM | 30 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:51:32 AM | 14 | 1332.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:51:32 AM | 11 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:51:32 AM | 73 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:51:32 AM | 23 | 1333.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:51:49 AM | 27 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:51:54 AM | 6 | 1332.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:52:06 AM | 47 | 1332.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:52:41 AM | 37 | 1332.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:52:41 AM | 74 | 1332.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:52:41 AM | 5 | 1331.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:52:44 AM | 9 | 1331.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:53:03 AM | 2 | 1331.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:53:17 AM | 11 | 1331.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:54:27 AM | 16 | 1332.50 | CEUX |
2
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 9:54:29 AM | 1 | 1332.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 9:54:46 AM | 42 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:54:46 AM | 12 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:54:46 AM | 30 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:54:46 AM | 7 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:54:46 AM | 3 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:54:48 AM | 9 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:54:48 AM | 1 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:54:48 AM | 31 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:54:48 AM | 28 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:54:48 AM | 18 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:55:15 AM | 36 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:55:26 AM | 2 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:05 AM | 72 | 1332.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:05 AM | 72 | 1332.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:05 AM | 29 | 1332.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:56:26 AM | 1 | 1332.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:27 AM | 1 | 1332.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:41 AM | 23 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:41 AM | 9 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:41 AM | 6 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:41 AM | 17 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:41 AM | 8 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:44 AM | 58 | 1332.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:56:54 AM | 50 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:54 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:54 AM | 8 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:54 AM | 74 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:54 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:54 AM | 74 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:54 AM | 33 | 1333.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:56:55 AM | 3 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:55 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:57 AM | 53 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:57 AM | 3 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:57 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:57 AM | 21 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:57 AM | 60 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:57 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:57 AM | 12 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:58 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:58 AM | 74 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:58 AM | 74 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:58 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:59 AM | 11 | 1333.00 | XCSE |
3
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 9:56:59 AM | 72 | 1333.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 9:56:59 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:59 AM | 74 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:56:59 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:00 AM | 3 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:00 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:00 AM | 3 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:00 AM | 3 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:00 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:00 AM | 75 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:00 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:00 AM | 44 | 1333.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:57:01 AM | 74 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:01 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:01 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:01 AM | 74 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:02 AM | 3 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:02 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:02 AM | 3 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:02 AM | 20 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:04 AM | 13 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:04 AM | 9 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:04 AM | 1 | 1333.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:07 AM | 15 | 1332.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:57:28 AM | 73 | 1332.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:57:28 AM | 24 | 1332.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 9:57:54 AM | 2 | 1332.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:58:26 AM | 5 | 1332.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:59:14 AM | 36 | 1332.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:59:14 AM | 27 | 1332.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:59:34 AM | 26 | 1332.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:59:34 AM | 7 | 1332.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:59:40 AM | 25 | 1331.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 9:59:40 AM | 71 | 1331.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 9:59:43 AM | 47 | 1331.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:00:04 AM | 20 | 1330.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:00:04 AM | 14 | 1330.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:00:04 AM | 35 | 1330.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:00:04 AM | 10 | 1330.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:00:04 AM | 18 | 1330.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:00:06 AM | 2 | 1330.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:00:18 AM | 71 | 1329.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:01:22 AM | 39 | 1331.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:01:23 AM | 42 | 1331.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:01:23 AM | 8 | 1331.00 | XCSE |
4
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 10:01:23 AM | 8 | 1331.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 10:02:00 AM | 4 | 1331.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:02:00 AM | 42 | 1331.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:02:11 AM | 23 | 1331.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:02:34 AM | 72 | 1330.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:02:34 AM | 71 | 1330.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:02:34 AM | 33 | 1330.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:02:55 AM | 43 | 1329.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:02:55 AM | 28 | 1329.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:02:58 AM | 10 | 1329.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:02:58 AM | 59 | 1329.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:02:58 AM | 23 | 1329.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:03:45 AM | 34 | 1329.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:03:45 AM | 8 | 1329.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:03:45 AM | 28 | 1329.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:03:45 AM | 24 | 1328.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:03:45 AM | 50 | 1328.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:04:21 AM | 66 | 1328.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:04:46 AM | 71 | 1328.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:04:50 AM | 23 | 1328.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:04:50 AM | 42 | 1328.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:04:50 AM | 4 | 1328.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:04:50 AM | 25 | 1328.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:29 AM | 70 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:29 AM | 21 | 1330.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:05:29 AM | 18 | 1330.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 58 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 39 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 11 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 12 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 42 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 1 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 12 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 13 | 1330.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 51 | 1330.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 25 | 1330.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:05:30 AM | 7 | 1330.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:05:53 AM | 75 | 1329.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:05:53 AM | 74 | 1329.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:05:53 AM | 23 | 1329.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:11:06 AM | 13 | 1331.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:11:12 AM | 25 | 1331.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:11:57 AM | 13 | 1331.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:11:57 AM | 10 | 1331.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:11:57 AM | 37 | 1331.50 | XCSE |
5
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 10:11:57 AM | 42 | 1331.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 10:12:51 AM | 73 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:12:56 AM | 15 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:12:56 AM | 12 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:12:56 AM | 19 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:12:56 AM | 69 | 1333.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:13:21 AM | 5 | 1333.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:13:21 AM | 68 | 1333.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:13:22 AM | 10 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:13:22 AM | 7 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:14:23 AM | 27 | 1334.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:14:23 AM | 1 | 1334.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:14:26 AM | 3 | 1334.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:14:32 AM | 6 | 1333.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:02 AM | 10 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:02 AM | 42 | 1334.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:02 AM | 42 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:02 AM | 75 | 1334.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:16:02 AM | 23 | 1334.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:16:02 AM | 39 | 1334.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:16:03 AM | 30 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:03 AM | 42 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:09 AM | 42 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:09 AM | 30 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:09 AM | 70 | 1334.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:16:27 AM | 30 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:27 AM | 42 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:27 AM | 58 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:27 AM | 6 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:47 AM | 42 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:47 AM | 10 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:16:48 AM | 27 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:17:03 AM | 37 | 1334.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:17:29 AM | 11 | 1335.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:17:44 AM | 16 | 1335.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:18:06 AM | 73 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:18:06 AM | 72 | 1334.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:18:06 AM | 23 | 1334.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:18:55 AM | 23 | 1334.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:20:26 AM | 42 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:20:26 AM | 1 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:20:26 AM | 2 | 1334.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:21:14 AM | 25 | 1336.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:22:04 AM | 73 | 1336.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:04 AM | 48 | 1336.00 | CEUX |
6
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 10:22:04 AM | 23 | 1336.00 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 10:22:04 AM | 23 | 1336.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:22:54 AM | 42 | 1336.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:54 AM | 11 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:54 AM | 41 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:55 AM | 12 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:55 AM | 1 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:55 AM | 58 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:55 AM | 12 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:55 AM | 11 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:57 AM | 73 | 1337.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:57 AM | 20 | 1337.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:57 AM | 35 | 1337.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:22:59 AM | 24 | 1337.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:23:06 AM | 60 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:23:06 AM | 15 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:23:06 AM | 25 | 1336.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:23:06 AM | 47 | 1336.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:23:06 AM | 9 | 1336.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:23:06 AM | 33 | 1336.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:23:57 AM | 69 | 1336.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:25:08 AM | 11 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:25:08 AM | 10 | 1336.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:25:21 AM | 71 | 1336.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:25:21 AM | 69 | 1335.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:25:21 AM | 27 | 1336.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:25:23 AM | 1 | 1336.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:25:28 AM | 73 | 1335.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:25:28 AM | 1 | 1336.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:26:45 AM | 23 | 1337.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:27:10 AM | 10 | 1337.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:27:10 AM | 42 | 1337.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:27:10 AM | 12 | 1337.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:27:46 AM | 74 | 1338.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:29:07 AM | 10 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:29:07 AM | 30 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:29:07 AM | 27 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:29:07 AM | 3 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:29:07 AM | 23 | 1338.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:30:35 AM | 69 | 1339.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:30:35 AM | 44 | 1339.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:30:35 AM | 28 | 1339.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:31:01 AM | 4 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:31:01 AM | 30 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:31:01 AM | 72 | 1338.50 | XCSE |
7
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 10:31:01 AM | 18 | 1338.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 10:31:01 AM | 42 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:31:01 AM | 58 | 1338.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:31:01 AM | 41 | 1338.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:31:01 AM | 32 | 1339.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:31:06 AM | 18 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:31:06 AM | 10 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:31:06 AM | 35 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:31:26 AM | 2 | 1338.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:32:32 AM | 73 | 1339.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:32:32 AM | 30 | 1339.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:32:32 AM | 19 | 1339.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:32:32 AM | 1 | 1339.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:32:32 AM | 29 | 1339.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:32:32 AM | 18 | 1339.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:32:32 AM | 3 | 1339.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:33:11 AM | 12 | 1340.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:33:11 AM | 2 | 1340.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:33:23 AM | 25 | 1340.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:34:20 AM | 71 | 1340.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:34:20 AM | 38 | 1340.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:34:20 AM | 20 | 1340.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:35:03 AM | 1 | 1340.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:35:03 AM | 1 | 1340.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:36:14 AM | 11 | 1340.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:36:14 AM | 26 | 1340.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:36:14 AM | 36 | 1340.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:36:14 AM | 3 | 1340.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:36:14 AM | 11 | 1340.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:37:11 AM | 70 | 1340.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:37:11 AM | 69 | 1340.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:38:01 AM | 37 | 1339.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:38:01 AM | 1 | 1339.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:38:21 AM | 74 | 1339.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:41:26 AM | 2 | 1341.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:42:17 AM | 71 | 1340.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:42:52 AM | 71 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:04 AM | 10 | 1341.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:04 AM | 69 | 1341.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:43:04 AM | 23 | 1341.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:43:04 AM | 26 | 1341.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 39 | 1341.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 25 | 1341.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 25 | 1341.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 45 | 1341.00 | XCSE |
8
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 3 | 1341.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 42 | 1341.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 10 | 1341.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 42 | 1341.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 71 | 1340.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 31 | 1340.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:43:11 AM | 24 | 1340.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:43:59 AM | 37 | 1341.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:59 AM | 23 | 1341.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:59 AM | 42 | 1341.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:59 AM | 26 | 1341.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:59 AM | 12 | 1341.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:59 AM | 11 | 1341.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:43:59 AM | 8 | 1341.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:44:50 AM | 75 | 1342.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:45:28 AM | 25 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:31 AM | 19 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:31 AM | 11 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:31 AM | 11 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:31 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:31 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:31 AM | 23 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:31 AM | 11 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:41 AM | 13 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:41 AM | 22 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:56 AM | 35 | 1343.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:45:56 AM | 26 | 1343.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:46:22 AM | 71 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:46:22 AM | 71 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:46:22 AM | 32 | 1343.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:46:22 AM | 24 | 1343.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:46:23 AM | 71 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:46:23 AM | 1 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:49:43 AM | 26 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:49:43 AM | 25 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:49:43 AM | 36 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:16 AM | 72 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:16 AM | 32 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:51:16 AM | 71 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:51:16 AM | 25 | 1343.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:51:16 AM | 27 | 1343.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:51:44 AM | 23 | 1342.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:51:47 AM | 12 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:47 AM | 36 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:47 AM | 14 | 1343.00 | XCSE |
9
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 10:51:47 AM | 19 | 1343.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 10:51:47 AM | 1 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:47 AM | 2 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:47 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:55 AM | 3 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:55 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:55 AM | 42 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:55 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:51:55 AM | 27 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:52:24 AM | 44 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:52:24 AM | 21 | 1342.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:52:24 AM | 49 | 1342.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:52:24 AM | 25 | 1342.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:54:10 AM | 2 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:10 AM | 27 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:10 AM | 42 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:10 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:10 AM | 4 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:10 AM | 9 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:45 AM | 19 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:45 AM | 17 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:45 AM | 2 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:45 AM | 12 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:45 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:54:56 AM | 72 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:55:58 AM | 4 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:55:58 AM | 1 | 1343.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:56:02 AM | 23 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:56:02 AM | 14 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:56:02 AM | 37 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:56:02 AM | 34 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:56:02 AM | 22 | 1343.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 10:57:00 AM | 23 | 1342.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 10:57:25 AM | 2 | 1342.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:58:13 AM | 72 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:58:13 AM | 25 | 1342.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:58:13 AM | 49 | 1342.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 10:58:43 AM | 12 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:58:43 AM | 23 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 10:59:26 AM | 28 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:01 AM | 19 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:01 AM | 23 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:01 AM | 1 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:01 AM | 1 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:01 AM | 42 | 1343.00 | XCSE |
10
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 11:00:01 AM | 33 | 1342.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 11:00:02 AM | 15 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:02 AM | 11 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:02 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:02 AM | 13 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:02 AM | 1 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:02 AM | 42 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:26 AM | 1 | 1342.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:00:45 AM | 12 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:45 AM | 13 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:45 AM | 12 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:45 AM | 65 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:45 AM | 12 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:45 AM | 4 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:00:45 AM | 75 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:02:26 AM | 11 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:02:27 AM | 47 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:02:27 AM | 7 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:02:27 AM | 3 | 1342.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:03:26 AM | 12 | 1342.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:03:26 AM | 2 | 1342.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:03:26 AM | 25 | 1342.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:03:27 AM | 1 | 1342.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:03:35 AM | 23 | 1342.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:03:35 AM | 3 | 1342.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:03:39 AM | 15 | 1342.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:03:39 AM | 4 | 1342.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:03:40 AM | 10 | 1342.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:04:26 AM | 1 | 1342.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:04:52 AM | 75 | 1342.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:04:59 AM | 28 | 1342.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:04:59 AM | 40 | 1342.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:04:59 AM | 12 | 1342.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:40 AM | 1 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:40 AM | 12 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:40 AM | 1 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:40 AM | 18 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:40 AM | 12 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:40 AM | 2 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:40 AM | 10 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:40 AM | 18 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:05:41 AM | 38 | 1343.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:05:41 AM | 21 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:05:44 AM | 11 | 1343.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:05:50 AM | 36 | 1343.00 | CEUX |
11
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 11:06:04 AM | 21 | 1343.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 11:06:37 AM | 2 | 1344.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:06:42 AM | 3 | 1344.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:06:42 AM | 7 | 1344.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:06:42 AM | 34 | 1344.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:08:26 AM | 4 | 1345.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:08:44 AM | 14 | 1346.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:08:48 AM | 1 | 1346.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:08:48 AM | 1 | 1346.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:08:51 AM | 13 | 1346.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:08:51 AM | 35 | 1346.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:08:51 AM | 35 | 1346.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:08:51 AM | 59 | 1346.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:09:12 AM | 26 | 1346.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:09:25 AM | 2 | 1346.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:09:25 AM | 1 | 1346.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:09:26 AM | 2 | 1346.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:09:26 AM | 15 | 1346.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:10:25 AM | 5 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:10:25 AM | 11 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:10:25 AM | 5 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:10:25 AM | 23 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:10:37 AM | 4 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:10:37 AM | 5 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:11:03 AM | 1 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:11:20 AM | 22 | 1347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:11:20 AM | 25 | 1347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:11:20 AM | 2 | 1347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:55 AM | 53 | 1348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:55 AM | 41 | 1348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:56 AM | 78 | 1348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:56 AM | 10 | 1348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:56 AM | 16 | 1348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:57 AM | 9 | 1348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:58 AM | 12 | 1347.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:58 AM | 26 | 1348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:58 AM | 26 | 1347.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:58 AM | 36 | 1347.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:12:58 AM | 23 | 1347.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:12:59 AM | 24 | 1347.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:59 AM | 12 | 1347.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:59 AM | 10 | 1347.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:12:59 AM | 22 | 1347.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 32 | 1347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 10 | 1347.50 | XCSE |
12
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 10 | 1347.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 31 | 1347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 11 | 1347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 32 | 1347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 42 | 1347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 5 | 1347.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 36 | 1347.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 4 | 1347.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 7 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 62 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 37 | 1347.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:13:05 AM | 2 | 1347.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:13:07 AM | 4 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:13:07 AM | 11 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:13:07 AM | 4 | 1347.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:14:23 AM | 26 | 1346.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:14:23 AM | 39 | 1346.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:14:45 AM | 12 | 1346.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:14:45 AM | 2 | 1346.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:16:26 AM | 1 | 1346.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 71 | 1348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 42 | 1348.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 12 | 1348.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 7 | 1348.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 10 | 1348.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 5 | 1348.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 12 | 1348.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 4 | 1348.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:18:27 AM | 63 | 1348.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:18:38 AM | 4 | 1349.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:19:00 AM | 61 | 1348.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:19:54 AM | 10 | 1349.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:19:54 AM | 64 | 1349.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:19:54 AM | 2 | 1349.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:19:54 AM | 1 | 1349.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:19:54 AM | 17 | 1349.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:19:58 AM | 13 | 1350.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:19:58 AM | 8 | 1350.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:20:01 AM | 71 | 1350.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:21:30 AM | 42 | 1351.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:21:30 AM | 23 | 1351.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:21:30 AM | 8 | 1351.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:22:34 AM | 9 | 1351.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:22:34 AM | 16 | 1351.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:22:34 AM | 30 | 1351.50 | CEUX |
13
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 11:22:34 AM | 1 | 1351.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 11:23:36 AM | 35 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:36 AM | 42 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:36 AM | 8 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:36 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:37 AM | 11 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:37 AM | 10 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:37 AM | 15 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:37 AM | 2 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:37 AM | 42 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:37 AM | 10 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:37 AM | 12 | 1352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:23:38 AM | 17 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:38 AM | 14 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:39 AM | 12 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:39 AM | 16 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:40 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:40 AM | 16 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:40 AM | 17 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:41 AM | 10 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:41 AM | 11 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:42 AM | 15 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:42 AM | 7 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:23:42 AM | 24 | 1,352.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:24:25 AM | 36 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:24:26 AM | 13 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:24:26 AM | 1 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:24:26 AM | 1 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:24:41 AM | 36 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:25:00 AM | 32 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:25:53 AM | 11 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:25:53 AM | 43 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:25:53 AM | 1 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:25:53 AM | 27 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:25:54 AM | 71 | 1,351.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:00 AM | 20 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:00 AM | 17 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:25 AM | 42 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:25 AM | 10 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:26 AM | 2 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:31 AM | 11 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:38 AM | 15 | 1,352.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:38 AM | 35 | 1,352.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:38 AM | 27 | 1,352.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:26:38 AM | 2 | 1,352.50 | XCSE |
14
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 11:26:46 AM | 36 | 1,352.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 11:26:47 AM | 5 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:26:54 AM | 5 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:26:54 AM | 5 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:26:54 AM | 12 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:27:15 AM | 23 | 1,352.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:27:27 AM | 70 | 1,351.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:27:27 AM | 74 | 1,349.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:27:27 AM | 70 | 1,351.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:27:27 AM | 29 | 1,351.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:27:27 AM | 24 | 1,351.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:27:31 AM | 23 | 1,351.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:28:25 AM | 72 | 1,350.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:28:40 AM | 9 | 1,348.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:28:40 AM | 69 | 1,349.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:28:40 AM | 69 | 1,350.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:28:40 AM | 28 | 1,350.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:28:40 AM | 23 | 1,350.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:29:11 AM | 67 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:29:11 AM | 67 | 1,349.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:29:11 AM | 1 | 1,348.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:29:11 AM | 71 | 1,348.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:29:15 AM | 74 | 1,347.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:29:15 AM | 26 | 1,348.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:29:56 AM | 75 | 1,347.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:30:36 AM | 49 | 1,348.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:32:07 AM | 22 | 1,348.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:34:05 AM | 3 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:34:05 AM | 37 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:34:05 AM | 4 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:34:35 AM | 1 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:34:35 AM | 12 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:34:45 AM | 12 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:34:55 AM | 12 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:37:25 AM | 53 | 1,348.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:37:25 AM | 18 | 1,348.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:37:25 AM | 2 | 1,348.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:37:25 AM | 18 | 1,348.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:37:25 AM | 22 | 1,348.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:37:25 AM | 34 | 1,348.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:39:05 AM | 17 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:39:05 AM | 40 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:39:05 AM | 37 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:39:19 AM | 1 | 1,351.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:39:19 AM | 10 | 1,351.00 | CEUX |
15
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 11:39:19 AM | 58 | 1,351.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 11:39:24 AM | 46 | 1,351.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:39:34 AM | 7 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:39:35 AM | 10 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:39:35 AM | 18 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:40:41 AM | 12 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:40:41 AM | 3 | 1,351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:42:25 AM | 33 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:42:25 AM | 16 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:42:25 AM | 1 | 1,352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:42:45 AM | 59 | 1,354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:42:45 AM | 35 | 1,354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:42:46 AM | 47 | 1,354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:43:10 AM | 13 | 1,355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:43:45 AM | 5 | 1,355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:43:45 AM | 13 | 1,355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:43:45 AM | 5 | 1,355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:44:14 AM | 69 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:14 AM | 25 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:14 AM | 1 | 1,355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 48 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 16 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 78 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 21 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 25 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 4 | 1,355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 4 | 1,355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 2 | 1,355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:44:15 AM | 43 | 1,355.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:44:16 AM | 23 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:34 AM | 23 | 1,355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:44:35 AM | 21 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:35 AM | 2 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:55 AM | 7 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:44:55 AM | 25 | 1,355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:45:13 AM | 59 | 1,354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:45:13 AM | 13 | 1,354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:45:13 AM | 17 | 1,354.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:45:13 AM | 56 | 1,354.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:45:13 AM | 30 | 1,354.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:45:13 AM | 32 | 1,354.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:45:19 AM | 23 | 1,353.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:45:22 AM | 51 | 1,353.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:45:22 AM | 74 | 1,353.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:45:22 AM | 4 | 1,354.00 | TQEX |
16
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 11:45:22 AM | 32 | 1,353.50 | AQEU |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 11:48:38 AM | 7 | 1,354.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:49:43 AM | 4 | 1,354.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:50:14 AM | 32 | 1,354.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:51:29 AM | 3 | 1,356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:51:48 AM | 2 | 1,357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:51:48 AM | 50 | 1,357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:51:48 AM | 29 | 1,357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:51:48 AM | 72 | 1,356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:51:48 AM | 26 | 1,356.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:51:51 AM | 70 | 1,357.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:51:51 AM | 29 | 1,357.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:52:05 AM | 15 | 1,357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:52:05 AM | 7 | 1,357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:53:44 AM | 75 | 1,359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:53:45 AM | 29 | 1,359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:53:50 AM | 50 | 1,359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:53:53 AM | 50 | 1,359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:53:58 AM | 54 | 1,359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:53:58 AM | 18 | 1,359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:53:58 AM | 23 | 1,359.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:54:04 AM | 11 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:54:04 AM | 10 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:54:04 AM | 42 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:54:04 AM | 10 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:54:07 AM | 50 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:54:17 AM | 70 | 1,361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:54:21 AM | 62 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:54:25 AM | 37 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:54:55 AM | 7 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:54:55 AM | 2 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:25 AM | 1 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:25 AM | 24 | 1,361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:43 AM | 24 | 1,361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:43 AM | 18 | 1,361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:43 AM | 23 | 1,361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:43 AM | 21 | 1,361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:58 AM | 70 | 1,360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:58 AM | 1 | 1,360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:55:58 AM | 55 | 1,360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:57:30 AM | 75 | 1,359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:57:30 AM | 69 | 1,360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 11:57:30 AM | 23 | 1,360.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 11:57:30 AM | 50 | 1,359.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 11:57:30 AM | 56 | 1,360.50 | AQEU |
17
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 11:59:25 AM | 11 | 1,359.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 11:59:25 AM | 10 | 1,359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:59:26 AM | 1 | 1,359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:59:35 AM | 18 | 1,360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:59:35 AM | 22 | 1,360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:59:35 AM | 10 | 1,360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 11:59:35 AM | 10 | 1,360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:01:26 PM | 1 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:02:02 PM | 12 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:02:26 PM | 2 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:02:26 PM | 1 | 1,363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:03:26 PM | 1 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:03:26 PM | 2 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:03:27 PM | 4 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:03:27 PM | 2 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:03:45 PM | 42 | 1,362.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:03:58 PM | 10 | 1,362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:03:58 PM | 12 | 1,362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:03:58 PM | 4 | 1,362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:04:26 PM | 1 | 1,362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:04:27 PM | 11 | 1,362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:04:27 PM | 10 | 1,362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:04:27 PM | 31 | 1,362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:05:25 PM | 1 | 1,362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:05:25 PM | 1 | 1,362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:05:25 PM | 1 | 1,362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:05:25 PM | 1 | 1,362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:05:26 PM | 4 | 1,362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:06:25 PM | 1 | 1,362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:06:34 PM | 1 | 1,363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:06:34 PM | 18 | 1,363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:06:40 PM | 12 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:06:40 PM | 22 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:06:40 PM | 36 | 1,363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:06:40 PM | 24 | 1,363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:06:40 PM | 26 | 1,362.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:07:09 PM | 12 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:09 PM | 35 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:09 PM | 17 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:09 PM | 30 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:09 PM | 5 | 1,363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:07:10 PM | 34 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:10 PM | 39 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:10 PM | 12 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:10 PM | 11 | 1,363.00 | XCSE |
18
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 12:07:10 PM | 10 | 1,363.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 12:07:10 PM | 10 | 1,363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:18 PM | 70 | 1,364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:07:19 PM | 30 | 1,364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:07:19 PM | 71 | 1,364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:07:21 PM | 70 | 1,364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:08:52 PM | 71 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:08:52 PM | 69 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:08:52 PM | 73 | 1,370.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:08:53 PM | 33 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:08:53 PM | 50 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:08:54 PM | 18 | 1,370.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:08:54 PM | 1 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:09:01 PM | 69 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:09:01 PM | 72 | 1,371.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:09:01 PM | 74 | 1,370.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:09:02 PM | 75 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:09:02 PM | 74 | 1,370.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:09:04 PM | 13 | 1,369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:09:04 PM | 69 | 1,369.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:09:06 PM | 60 | 1,369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:09:06 PM | 74 | 1,369.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:09:06 PM | 1 | 1,369.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:13:05 PM | 10 | 1,372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:13:49 PM | 11 | 1,372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:13:52 PM | 11 | 1,372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:13:52 PM | 11 | 1,372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:13:52 PM | 28 | 1,371.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:13:59 PM | 17 | 1,372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:14:07 PM | 74 | 1,372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:14:07 PM | 62 | 1,372.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:14:07 PM | 23 | 1,372.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:14:27 PM | 70 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:14:27 PM | 24 | 1,370.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:14:27 PM | 45 | 1,370.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:14:27 PM | 17 | 1,371.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:15:25 PM | 69 | 1,369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:15:25 PM | 28 | 1,369.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:17:25 PM | 3 | 1,371.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:17:25 PM | 2 | 1,371.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:17:25 PM | 2 | 1,371.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:17:26 PM | 38 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:17:26 PM | 37 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:17:26 PM | 39 | 1,371.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:17:26 PM | 25 | 1,370.50 | AQEU |
19
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 12:18:04 PM | 14 | 1,370.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 12:18:04 PM | 59 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:18:04 PM | 20 | 1,370.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:18:04 PM | 18 | 1,370.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:18:04 PM | 41 | 1,369.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:18:07 PM | 6 | 1,369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:18:07 PM | 68 | 1,369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:18:11 PM | 44 | 1,368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:18:11 PM | 26 | 1,368.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:21:00 PM | 23 | 1,370.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:21:25 PM | 2 | 1,369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:21:25 PM | 70 | 1,369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:21:25 PM | 14 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:21:25 PM | 2 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:21:25 PM | 7 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:21:25 PM | 46 | 1,369.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:21:51 PM | 1 | 1,368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:21:51 PM | 4 | 1,368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:25:25 PM | 23 | 1,369.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:25:26 PM | 2 | 1,369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:25:26 PM | 1 | 1,369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:27:26 PM | 75 | 1,370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:27:26 PM | 23 | 1,370.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:28:07 PM | 6 | 1,370.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:28:07 PM | 11 | 1,370.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:28:26 PM | 1 | 1,370.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:29:53 PM | 3 | 1,370.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 1 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 30 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 30 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 1 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 11 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 27 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 10 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 2 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 43 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:08 PM | 10 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:09 PM | 11 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:09 PM | 12 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:09 PM | 12 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:09 PM | 34 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:09 PM | 12 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:09 PM | 30 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:09 PM | 30 | 1,371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:22 PM | 73 | 1,369.50 | XCSE |
20
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 12:30:22 PM | 75 | 1,369.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 12:30:22 PM | 41 | 1,369.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:30:45 PM | 72 | 1,368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:45 PM | 38 | 1,368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:30:47 PM | 74 | 1,367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:47 PM | 40 | 1,367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:30:55 PM | 75 | 1,366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:55 PM | 73 | 1,366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:30:57 PM | 70 | 1,365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:30:57 PM | 75 | 1,365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:31:29 PM | 20 | 1,364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:31:29 PM | 35 | 1,365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:31:29 PM | 14 | 1,364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:31:29 PM | 35 | 1,364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:36:45 PM | 1 | 1,366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:36:45 PM | 11 | 1,366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:36:45 PM | 1 | 1,366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:37:20 PM | 23 | 1,365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:37:20 PM | 23 | 1,365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:37:20 PM | 40 | 1,365.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:37:20 PM | 26 | 1,365.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:38:17 PM | 24 | 1,365.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:38:37 PM | 10 | 1,365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:38:37 PM | 30 | 1,365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:38:37 PM | 42 | 1,365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:38:37 PM | 12 | 1,365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:38:37 PM | 27 | 1,364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:38:37 PM | 14 | 1,364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:39:10 PM | 3 | 1,365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:39:14 PM | 1 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:40:26 PM | 63 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:40:26 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:40:35 PM | 2 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:40:35 PM | 94 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:41:16 PM | 74 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:41:21 PM | 52 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:41:21 PM | 58 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:41:21 PM | 40 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:41:21 PM | 27 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:43:51 PM | 23 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:43:51 PM | 75 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:43:51 PM | 74 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:45:47 PM | 47 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:45:47 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:45:47 PM | 1 | 1367.00 | XCSE |
21
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 12:45:47 PM | 26 | 1367.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 12:45:47 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 8 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 71 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 19 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 69 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:47:15 PM | 42 | 1365.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:48:26 PM | 74 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:48:27 PM | 20 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:48:27 PM | 49 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:48:42 PM | 6 | 1365.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:49:35 PM | 73 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:52:26 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:52:26 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:52:26 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:52:26 PM | 19 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:53:23 PM | 71 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:53:26 PM | 1 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 2 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 75 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 21 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 42 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 37 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 10 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 42 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 67 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 30 | 1365.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:54:25 PM | 41 | 1365.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 12:55:40 PM | 44 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:58:47 PM | 23 | 1365.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 12:59:10 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:59:10 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:59:10 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 12:59:37 PM | 71 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:00:14 PM | 4 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:00:14 PM | 1 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:00:14 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:00:14 PM | 70 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:00:14 PM | 41 | 1366.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:01:14 PM | 74 | 1368.00 | XCSE |
22
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 1:01:14 PM | 73 | 1368.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 1:02:24 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:02:26 PM | 27 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:02:57 PM | 69 | 1368.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:03:24 PM | 21 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:03:24 PM | 30 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:03:24 PM | 15 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:03:24 PM | 28 | 1367.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:03:26 PM | 72 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:03:26 PM | 1 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:03:26 PM | 70 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:04:06 PM | 6 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:04:06 PM | 69 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:04:06 PM | 72 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:04:08 PM | 71 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:08:53 PM | 25 | 1369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:08:53 PM | 10 | 1369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:08:56 PM | 72 | 1369.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:09:58 PM | 34 | 1370.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:09:58 PM | 42 | 1370.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:09:58 PM | 18 | 1370.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:10:00 PM | 75 | 1370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:10:00 PM | 36 | 1369.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:10:00 PM | 23 | 1370.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:10:00 PM | 25 | 1370.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:10:01 PM | 75 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:10:03 PM | 9 | 1369.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:10:03 PM | 18 | 1369.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:10:35 PM | 35 | 1368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:10:35 PM | 34 | 1368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:10:45 PM | 74 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:11:14 PM | 69 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:11:18 PM | 66 | 1371.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:11:18 PM | 48 | 1372.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:11:21 PM | 23 | 1372.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:12:10 PM | 51 | 1373.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:12:10 PM | 28 | 1373.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:12:24 PM | 43 | 1372.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:12:24 PM | 29 | 1372.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:12:27 PM | 50 | 1371.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:12:27 PM | 44 | 1371.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:12:32 PM | 25 | 1371.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:12:54 PM | 41 | 1370.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:15:58 PM | 5 | 1371.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:15:58 PM | 18 | 1371.50 | CEUX |
23
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 1:16:13 PM | 27 | 1372.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 1:19:25 PM | 3 | 1372.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:19:25 PM | 4 | 1372.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:19:48 PM | 30 | 1373.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:19:48 PM | 17 | 1373.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:20:25 PM | 1 | 1372.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:20:25 PM | 1 | 1372.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:20:25 PM | 10 | 1372.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:20:42 PM | 2 | 1373.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:20:42 PM | 15 | 1373.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:21:06 PM | 12 | 1373.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:21:06 PM | 10 | 1373.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:21:55 PM | 73 | 1373.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:21:55 PM | 42 | 1373.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:21:55 PM | 17 | 1373.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:21:55 PM | 35 | 1373.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:21:55 PM | 61 | 1373.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:21:55 PM | 28 | 1373.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:21:56 PM | 69 | 1372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:21:56 PM | 20 | 1372.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:21:56 PM | 3 | 1372.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:21:56 PM | 23 | 1372.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:21:56 PM | 26 | 1372.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:22:15 PM | 70 | 1372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:22:15 PM | 26 | 1372.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:23:25 PM | 49 | 1372.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:24:24 PM | 71 | 1372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:25:41 PM | 23 | 1372.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:26:18 PM | 73 | 1372.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:26:35 PM | 9 | 1371.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:26:37 PM | 38 | 1371.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:26:49 PM | 60 | 1371.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:26:49 PM | 43 | 1371.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:26:50 PM | 75 | 1370.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:26:50 PM | 24 | 1370.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:29:19 PM | 9 | 1370.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:29:27 PM | 8 | 1369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:29:31 PM | 1 | 1369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:30:02 PM | 5 | 1369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:30:02 PM | 9 | 1369.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:30:25 PM | 52 | 1369.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:30:27 PM | 75 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:30:30 PM | 2 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:30:31 PM | 10 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:30:59 PM | 19 | 1367.50 | CEUX |
24
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 1:31:07 PM | 27 | 1367.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 1:31:15 PM | 44 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:31:15 PM | 27 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:32:30 PM | 70 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:32:30 PM | 71 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:32:30 PM | 46 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:32:30 PM | 24 | 1367.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:33:04 PM | 75 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:33:04 PM | 57 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:34:45 PM | 75 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:34:45 PM | 58 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:35:38 PM | 72 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:35:38 PM | 23 | 1367.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:37:27 PM | 23 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:39:26 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:39:26 PM | 71 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:39:26 PM | 59 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:39:26 PM | 24 | 1367.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:39:26 PM | 24 | 1367.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:39:30 PM | 70 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:40:21 PM | 73 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:40:21 PM | 1 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:40:21 PM | 43 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:40:31 PM | 57 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:41:00 PM | 69 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:41:00 PM | 25 | 1365.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:41:08 PM | 72 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:41:08 PM | 4 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:41:08 PM | 29 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:41:40 PM | 14 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:42:28 PM | 41 | 1363.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:43:08 PM | 35 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:44:48 PM | 50 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:44:48 PM | 26 | 1367.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:44:49 PM | 74 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:44:49 PM | 35 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:44:49 PM | 56 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:44:54 PM | 75 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:46:26 PM | 26 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:46:41 PM | 74 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:48:35 PM | 34 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:48:41 PM | 2 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:48:41 PM | 8 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:49:03 PM | 30 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:50:23 PM | 75 | 1368.00 | XCSE |
25
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 1:50:23 PM | 28 | 1368.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 1:50:23 PM | 42 | 1368.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:50:23 PM | 41 | 1368.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:50:25 PM | 19 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:50:25 PM | 25 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:50:25 PM | 2 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:50:25 PM | 1 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:50:25 PM | 74 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:50:25 PM | 23 | 1368.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:51:25 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:51:25 PM | 2 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:51:25 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:51:25 PM | 2 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:51:25 PM | 2 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:51:34 PM | 29 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:52:05 PM | 17 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:52:05 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:52:05 PM | 30 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:52:05 PM | 8 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:52:05 PM | 4 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:52:55 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:52:57 PM | 18 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:53:11 PM | 6 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:53:15 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:53:15 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:53:15 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:53:37 PM | 18 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:03 PM | 1 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:15 PM | 1 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:15 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:15 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:15 PM | 18 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:15 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:15 PM | 18 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:55 PM | 14 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:54:55 PM | 18 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:55:28 PM | 5 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:55:28 PM | 72 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:55:28 PM | 18 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:55:28 PM | 40 | 1369.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:55:28 PM | 12 | 1369.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:55:28 PM | 22 | 1369.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:55:42 PM | 48 | 1368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:56:55 PM | 73 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:56:55 PM | 18 | 1368.50 | XCSE |
26
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 1:56:55 PM | 1 | 1368.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 1:56:55 PM | 4 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:56:55 PM | 40 | 1368.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 1:57:31 PM | 55 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:58:25 PM | 8 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:58:25 PM | 3 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:58:25 PM | 3 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:25 PM | 15 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:25 PM | 2 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:25 PM | 39 | 1368.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:59:26 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:26 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:26 PM | 17 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:26 PM | 18 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:26 PM | 3 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:26 PM | 4 | 1368.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:47 PM | 70 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:47 PM | 44 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 1:59:47 PM | 39 | 1367.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 1:59:49 PM | 49 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:49 PM | 23 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 1:59:49 PM | 25 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:00:32 PM | 75 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:00:32 PM | 30 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:01:36 PM | 71 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:03:52 PM | 30 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:03:52 PM | 40 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:04:34 PM | 23 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:06:32 PM | 10 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:32 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:32 PM | 8 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:32 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:32 PM | 16 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:32 PM | 10 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:33 PM | 23 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:44 PM | 48 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:44 PM | 6 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:44 PM | 37 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:44 PM | 8 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:44 PM | 7 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:06:44 PM | 15 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:06:44 PM | 10 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:06:49 PM | 36 | 1363.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:06:49 PM | 5 | 1363.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:06:49 PM | 39 | 1363.50 | AQEU |
27
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:07:26 PM | 74 | 1363.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:08:34 PM | 71 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:08:34 PM | 23 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:09:50 PM | 72 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:10:25 PM | 75 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:11:09 PM | 75 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:11:17 PM | 41 | 1363.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:11:18 PM | 72 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:11:18 PM | 72 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:11:18 PM | 20 | 1363.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:11:18 PM | 19 | 1363.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:12:34 PM | 39 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:13:25 PM | 42 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:13:25 PM | 4 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:13:25 PM | 10 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:13:25 PM | 12 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:13:25 PM | 71 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:13:25 PM | 26 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:13:33 PM | 69 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:13:33 PM | 62 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:15:12 PM | 69 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:15:12 PM | 40 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:15:16 PM | 2 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:15:16 PM | 13 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:16:57 PM | 69 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:16:57 PM | 40 | 1363.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:17:27 PM | 72 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:17:27 PM | 6 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:17:27 PM | 75 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:17:27 PM | 47 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:17:27 PM | 41 | 1366.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:17:41 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:17:41 PM | 21 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:17:44 PM | 74 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:17:54 PM | 71 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:18:25 PM | 72 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:19:09 PM | 73 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:19:09 PM | 38 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:19:09 PM | 2 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:19:49 PM | 23 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:19:59 PM | 74 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:20:00 PM | 16 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:20:14 PM | 59 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:21:29 PM | 73 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:21:29 PM | 23 | 1362.50 | CEUX |
28
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:21:53 PM | 75 | 1363.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:21:53 PM | 30 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:22:19 PM | 10 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:22:19 PM | 18 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:22:19 PM | 30 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:22:54 PM | 68 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:23:25 PM | 42 | 1363.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:23:52 PM | 72 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:23:52 PM | 32 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:24:40 PM | 70 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:25:12 PM | 1 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:25:12 PM | 27 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:25:15 PM | 8 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:25:41 PM | 65 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:25:41 PM | 9 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:25:41 PM | 43 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:26:18 PM | 75 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:26:18 PM | 71 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:26:18 PM | 23 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:26:18 PM | 36 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:26:18 PM | 9 | 1360.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:26:18 PM | 29 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:26:19 PM | 60 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:26:30 PM | 25 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:26:30 PM | 30 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:27:30 PM | 70 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:27:30 PM | 31 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:27:55 PM | 5 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:27:55 PM | 66 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:27:55 PM | 21 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:27:55 PM | 10 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:27:55 PM | 31 | 1364.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:29:33 PM | 71 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:29:33 PM | 5 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:29:33 PM | 2 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:29:33 PM | 34 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:29:52 PM | 15 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:29:52 PM | 9 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:30:00 PM | 1 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:00 PM | 15 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:00 PM | 55 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:00 PM | 25 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:30:02 PM | 23 | 1363.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:30:10 PM | 19 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:10 PM | 53 | 1362.50 | XCSE |
29
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:30:10 PM | 14 | 1362.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:30:10 PM | 9 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:30:11 PM | 72 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:11 PM | 44 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:30:11 PM | 6 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:30:12 PM | 23 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:12 PM | 50 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:12 PM | 43 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:30:13 PM | 52 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:41 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:41 PM | 22 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:41 PM | 34 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:41 PM | 3 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:42 PM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:30:42 PM | 3 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:30:42 PM | 8 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:30:42 PM | 12 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:30:47 PM | 10 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:30:48 PM | 15 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:30:48 PM | 3 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:30:48 PM | 21 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:31:10 PM | 57 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:10 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:10 PM | 35 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:31:13 PM | 18 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:13 PM | 33 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:31:18 PM | 48 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:18 PM | 25 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:31:18 PM | 34 | 1358.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:31:19 PM | 42 | 1358.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:31 PM | 31 | 1358.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:31 PM | 3 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:31 PM | 7 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:31 PM | 60 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:31 PM | 1 | 1356.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:31:31 PM | 33 | 1357.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:31:31 PM | 12 | 1357.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:31:35 PM | 26 | 1358.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:32:10 PM | 22 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:32:10 PM | 17 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:32:10 PM | 68 | 1356.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:32:10 PM | 62 | 1358.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:32:10 PM | 24 | 1356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:32:10 PM | 30 | 1357.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:32:10 PM | 29 | 1357.00 | AQEU |
30
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:33:01 PM | 23 | 1358.00 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:33:14 PM | 74 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:33:27 PM | 17 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:33:27 PM | 10 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:33:27 PM | 72 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:33:27 PM | 21 | 1357.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:33:27 PM | 25 | 1357.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:33:27 PM | 23 | 1357.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:33:27 PM | 23 | 1358.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 74 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 22 | 1355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 10 | 1356.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 20 | 1356.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 50 | 1355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 11 | 1355.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 33 | 1356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 1 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 4 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 2 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 2 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 1 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 1 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 16 | 1355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 20 | 1355.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 2 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 1 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 11 | 1355.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 24 | 1355.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:34:25 PM | 14 | 1355.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:34:26 PM | 39 | 1355.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:27 PM | 23 | 1355.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:27 PM | 59 | 1355.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:57 PM | 20 | 1355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:57 PM | 30 | 1355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:57 PM | 10 | 1355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:57 PM | 12 | 1355.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:59 PM | 12 | 1354.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:59 PM | 10 | 1354.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:34:59 PM | 20 | 1354.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:34:59 PM | 6 | 1354.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:35:00 PM | 20 | 1354.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:30 PM | 32 | 1354.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:31 PM | 42 | 1354.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:31 PM | 20 | 1353.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:31 PM | 20 | 1354.00 | XCSE |
31
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:35:31 PM | 45 | 1354.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:35:31 PM | 30 | 1354.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:31 PM | 49 | 1354.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:35:31 PM | 29 | 1354.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:35:31 PM | 23 | 1354.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:35:41 PM | 11 | 1354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:41 PM | 3 | 1354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:41 PM | 42 | 1354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:41 PM | 12 | 1354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:41 PM | 21 | 1354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:35:41 PM | 2 | 1354.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:36:21 PM | 30 | 1353.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:36:21 PM | 75 | 1354.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:36:21 PM | 45 | 1353.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:36:21 PM | 71 | 1352.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:36:21 PM | 69 | 1353.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:36:21 PM | 24 | 1352.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:36:27 PM | 57 | 1353.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:36:30 PM | 71 | 1352.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:36:31 PM | 73 | 1352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:36:43 PM | 71 | 1351.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:37:04 PM | 69 | 1353.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:37:13 PM | 23 | 1353.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:37:44 PM | 1 | 1353.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:37:44 PM | 23 | 1353.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:37:48 PM | 72 | 1352.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:37:48 PM | 8 | 1352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:37:48 PM | 15 | 1352.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:37:48 PM | 25 | 1352.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:38:53 PM | 16 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:38:53 PM | 2 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:01 PM | 42 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:01 PM | 10 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:01 PM | 30 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:01 PM | 23 | 1357.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:39:02 PM | 17 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:02 PM | 10 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:02 PM | 9 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:02 PM | 11 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:02 PM | 69 | 1357.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:39:14 PM | 69 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:15 PM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:15 PM | 14 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:15 PM | 48 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:15 PM | 43 | 1357.00 | TQEX |
32
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:39:21 PM | 2 | 1356.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:39:22 PM | 71 | 1356.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:39:32 PM | 11 | 1355.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:39:59 PM | 9 | 1357.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:40:03 PM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:40:15 PM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:40:31 PM | 9 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:40:35 PM | 11 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:40:44 PM | 72 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:40:44 PM | 75 | 1358.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:41:05 PM | 38 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:05 PM | 4 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:05 PM | 11 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:05 PM | 19 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:05 PM | 22 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:33 PM | 42 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:33 PM | 2 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:51 PM | 72 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:51 PM | 9 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:41:51 PM | 54 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:41:51 PM | 30 | 1359.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:41:52 PM | 7 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:54 PM | 9 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:41:54 PM | 16 | 1358.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:42:23 PM | 4 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:42:23 PM | 2 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:42:23 PM | 63 | 1359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:42:23 PM | 15 | 1359.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:42:27 PM | 15 | 1359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:42:27 PM | 24 | 1359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:43:11 PM | 3 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:43:11 PM | 11 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:43:25 PM | 44 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:43:25 PM | 50 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:43:25 PM | 57 | 1359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:43:26 PM | 19 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:43:26 PM | 75 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:43:56 PM | 10 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:44:04 PM | 10 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:44:04 PM | 10 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:44:04 PM | 37 | 1359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 23 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 31 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 10 | 1358.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 42 | 1358.00 | XCSE |
33
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 11 | 1358.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 44 | 1359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 10 | 1358.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 17 | 1358.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 23 | 1358.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:44:27 PM | 26 | 1359.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:45:13 PM | 12 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:13 PM | 3 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:13 PM | 4 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:13 PM | 56 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:13 PM | 11 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:13 PM | 16 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:13 PM | 10 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:26 PM | 3 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:26 PM | 10 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:26 PM | 10 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:45 PM | 42 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:45 PM | 10 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:45 PM | 3 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:45 PM | 23 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:45 PM | 16 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:45:49 PM | 5 | 1358.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:47:06 PM | 10 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:47:06 PM | 42 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:47:06 PM | 11 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:47:06 PM | 68 | 1359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:48:12 PM | 74 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:48:12 PM | 24 | 1359.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:48:12 PM | 35 | 1359.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:48:24 PM | 2 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:48:24 PM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:48:24 PM | 5 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:48:24 PM | 2 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:48:24 PM | 4 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:49:27 PM | 69 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:49:51 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:49:51 PM | 19 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:49:51 PM | 42 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:50:04 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:50:41 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:50:41 PM | 42 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:50:45 PM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:52:26 PM | 1 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:53:28 PM | 65 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:53:28 PM | 7 | 1361.50 | XCSE |
34
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:53:28 PM | 36 | 1361.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:53:46 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:53:46 PM | 9 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:53:51 PM | 69 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:53:52 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:53:52 PM | 42 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:07 PM | 14 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:07 PM | 28 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 71 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 24 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 1 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 72 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 28 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 75 | 1359.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 14 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 58 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 10 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 16 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 24 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:54:26 PM | 28 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:55:21 PM | 1 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:55:40 PM | 24 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:55:40 PM | 7 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:55:40 PM | 3 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:55:40 PM | 2 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:55:40 PM | 10 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:55:48 PM | 17 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:55:59 PM | 42 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:55:59 PM | 11 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:55:59 PM | 11 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:00 PM | 1 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:00 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:00 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:13 PM | 72 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:13 PM | 9 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:56:13 PM | 26 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 74 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 10 | 1359.00 | XCSE |
35
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 32 | 1360.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 11 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 30 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 70 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 34 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 36 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 4 | 1359.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 8 | 1358.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 10 | 1359.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 10 | 1359.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 7 | 1359.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:56:16 PM | 35 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:56:21 PM | 63 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:25 PM | 20 | 1358.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:25 PM | 8 | 1358.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:25 PM | 20 | 1358.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:25 PM | 10 | 1358.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:25 PM | 2 | 1358.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:25 PM | 15 | 1358.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:37 PM | 47 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:37 PM | 22 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:37 PM | 6 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:37 PM | 14 | 1357.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:37 PM | 40 | 1357.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:37 PM | 11 | 1357.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:37 PM | 7 | 1357.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:37 PM | 3 | 1357.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:45 PM | 6 | 1356.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:56:50 PM | 7 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:50 PM | 20 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:50 PM | 32 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:50 PM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:56:50 PM | 30 | 1356.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:57:10 PM | 23 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:57:10 PM | 17 | 1357.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:57:10 PM | 18 | 1357.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:57:10 PM | 25 | 1357.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 2:57:13 PM | 19 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:57:13 PM | 42 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:57:13 PM | 49 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:57:13 PM | 14 | 1356.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:57:18 PM | 42 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:57:18 PM | 6 | 1356.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:57:18 PM | 19 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:57:18 PM | 19 | 1356.00 | CEUX |
36
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 2:57:56 PM | 67 | 1356.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 2:58:20 PM | 4 | 1356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:58:20 PM | 1 | 1356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:58:28 PM | 20 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:28 PM | 27 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:28 PM | 10 | 1356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:58:30 PM | 10 | 1356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:58:31 PM | 12 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:31 PM | 42 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:31 PM | 33 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:31 PM | 29 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:31 PM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:31 PM | 11 | 1357.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:31 PM | 8 | 1356.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 2:58:31 PM | 23 | 1356.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 2:58:58 PM | 31 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:58 PM | 11 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:58 PM | 42 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:58 PM | 10 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:59 PM | 10 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:58:59 PM | 12 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:59:00 PM | 42 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:59:00 PM | 11 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:59:00 PM | 42 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:59:00 PM | 11 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:59:00 PM | 12 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:59:00 PM | 12 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 2:59:01 PM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:00:00 PM | 75 | 1357.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:00:00 PM | 10 | 1357.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:01:16 PM | 25 | 1358.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:01:16 PM | 10 | 1358.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:01:16 PM | 10 | 1358.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:01:16 PM | 20 | 1358.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:02:31 PM | 74 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:02:31 PM | 23 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:02:31 PM | 34 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:03:00 PM | 4 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:03:00 PM | 70 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:03:35 PM | 74 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:04:12 PM | 9 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:04:12 PM | 8 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:05:30 PM | 3 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:06:03 PM | 2 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:06:34 PM | 4 | 1361.50 | CEUX |
37
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:07:41 PM | 1 | 1362.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:07:41 PM | 10 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:07:54 PM | 39 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:07:54 PM | 41 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:07:55 PM | 2 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:08:23 PM | 7 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:08:23 PM | 3 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:08:23 PM | 20 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:08:58 PM | 10 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:08:59 PM | 10 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:09:01 PM | 38 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:09:01 PM | 1 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:09:01 PM | 7 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:09:15 PM | 6 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:09:49 PM | 35 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 66 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 15 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 27 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 71 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 71 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 42 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 36 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 69 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 1 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 7 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 26 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 15 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 12 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 31 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:10:05 PM | 19 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:10:08 PM | 28 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:10:28 PM | 7 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:10:31 PM | 20 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:10:53 PM | 2 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:23 PM | 70 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:11:37 PM | 10 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:37 PM | 18 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:37 PM | 11 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:37 PM | 72 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:37 PM | 42 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:44 PM | 42 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:44 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:44 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:45 PM | 11 | 1362.50 | XCSE |
38
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:11:45 PM | 10 | 1362.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:11:45 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:45 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:11:45 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:12:12 PM | 20 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:12:17 PM | 24 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:12:17 PM | 24 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:12:17 PM | 6 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:12:30 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:12:30 PM | 42 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:12:30 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:12:30 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:12:31 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:12:31 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:15 PM | 2 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:50 PM | 21 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:13:50 PM | 1 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:13:50 PM | 20 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:13:50 PM | 32 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 30 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 42 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 12 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 12 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 70 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:58 PM | 28 | 1362.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:13:59 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:59 PM | 10 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:59 PM | 10 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:13:59 PM | 10 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:14:01 PM | 12 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:15:10 PM | 73 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:15:26 PM | 4 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:15:26 PM | 3 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:15:26 PM | 74 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:15:26 PM | 24 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:15:26 PM | 27 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:17:03 PM | 71 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 42 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 2 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 10 | 1364.50 | XCSE |
39
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 11 | 1364.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 33 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 73 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 2 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 25 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 8 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:18:23 PM | 15 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:18:58 PM | 5 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:18:59 PM | 23 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:19:03 PM | 36 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:19:05 PM | 23 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:19:09 PM | 22 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:19:26 PM | 1 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:19:46 PM | 12 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:19:46 PM | 10 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:19:46 PM | 13 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:19:53 PM | 11 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:19:53 PM | 2 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:20:02 PM | 60 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:20:02 PM | 14 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:20:02 PM | 17 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:20:02 PM | 33 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:20:47 PM | 26 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 69 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 42 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 69 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 2 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 22 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 36 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 4 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 3 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 32 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 68 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 4 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 25 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 2 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 9 | 1363.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:21:07 PM | 16 | 1363.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:21:29 PM | 10 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:21:44 PM | 4 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:22:00 PM | 24 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:22:00 PM | 23 | 1363.50 | CEUX |
40
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:22:00 PM | 10 | 1363.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:22:00 PM | 25 | 1363.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:22:33 PM | 31 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:22:33 PM | 69 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:22:33 PM | 10 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:22:33 PM | 10 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:23:02 PM | 12 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:24:03 PM | 69 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:24:13 PM | 23 | 1363.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:25:26 PM | 3 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:26 PM | 9 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:26 PM | 1 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:26 PM | 8 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:26 PM | 15 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 30 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 42 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 1 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 12 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 72 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 33 | 1363.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 10 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 1 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 10 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 4 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 10 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 2 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 10 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 20 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:37 PM | 4 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:25:42 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:42 PM | 12 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:42 PM | 30 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:42 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:42 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:42 PM | 10 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:25:42 PM | 22 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 30 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 72 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 42 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 33 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 36 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 11 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 11 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 65 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 6 | 1361.50 | CEUX |
41
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 25 | 1362.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:26:17 PM | 44 | 1362.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:28:25 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:25 PM | 4 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:28:31 PM | 3 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 3 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 38 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 42 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 7 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 42 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 15 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 1 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:28:37 PM | 10 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:28:38 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:38 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:38 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:38 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:38 PM | 30 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:39 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:28:44 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:03 PM | 12 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:29:03 PM | 15 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:29:20 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:20 PM | 42 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:20 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:20 PM | 24 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:20 PM | 16 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:20 PM | 38 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:29:20 PM | 6 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 40 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 40 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 40 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 4 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:21 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:29:23 PM | 71 | 1360.50 | XCSE |
42
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:29:35 PM | 1 | 1360.50 | AQEU |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:29:47 PM | 2 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 17 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 71 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 69 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 28 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 30 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 72 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 17 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 50 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 75 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 7 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 23 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 3 | 1359.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:30:05 PM | 31 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:31:40 PM | 18 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 4 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 18 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 30 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 42 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 1 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 4 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 23 | 1360.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 1 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:32:01 PM | 27 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 42 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 26 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 32 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 6 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 42 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:02 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:04 PM | 18 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:04 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:04 PM | 42 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:04 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:04 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:11 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:11 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:11 PM | 42 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:11 PM | 17 | 1361.00 | XCSE |
43
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:32:11 PM | 11 | 1361.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:32:26 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:26 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:26 PM | 21 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:32:26 PM | 25 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:34:27 PM | 73 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:34:27 PM | 70 | 1363.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:34:56 PM | 70 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:36:25 PM | 2 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:36:26 PM | 2 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:36:27 PM | 3 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:36:52 PM | 6 | 1364.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:37:11 PM | 36 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:38:20 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:38:20 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:38:20 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:38:20 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:38:20 PM | 29 | 1366.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:38:20 PM | 14 | 1365.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:39:37 PM | 74 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:39:49 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:39:49 PM | 3 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:40:00 PM | 35 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:40:00 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:40:00 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:40:00 PM | 50 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:40:00 PM | 20 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:40:00 PM | 9 | 1365.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:40:00 PM | 24 | 1366.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:40:00 PM | 36 | 1366.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:40:29 PM | 10 | 1365.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:41:26 PM | 8 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:41:57 PM | 2 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:41:57 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:41:57 PM | 4 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:42:25 PM | 1 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:42:25 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:42:25 PM | 2 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:42:25 PM | 1 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:42:27 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:42:27 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:42:27 PM | 2 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:42:28 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:42:28 PM | 5 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:42:37 PM | 94 | 1365.50 | XCSE |
44
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:43:26 PM | 2 | 1366.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:44:26 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:26 PM | 36 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:27 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:27 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:27 PM | 2 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:27 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:27 PM | 4 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:27 PM | 4 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 42 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 72 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 29 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 69 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 11 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 7 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 5 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 8 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 6 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 2 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 7 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 8 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 18 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 15 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 5 | 1364.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 2 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 59 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 9 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 7 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 23 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 25 | 1365.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:44:49 PM | 13 | 1365.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:44:50 PM | 20 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:44:51 PM | 50 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:45:20 PM | 3 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:45:20 PM | 55 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:45:20 PM | 17 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:45:20 PM | 36 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:45:20 PM | 37 | 1366.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:46:08 PM | 72 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:08 PM | 34 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:08 PM | 40 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:20 PM | 72 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:20 PM | 71 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:20 PM | 24 | 1367.50 | TQEX |
45
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:46:27 PM | 9 | 1367.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 8 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 14 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 42 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 30 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 75 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 36 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 20 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 36 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 4 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 50 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 17 | 1367.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:46:58 PM | 6 | 1367.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:46:59 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:59 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:59 PM | 22 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:46:59 PM | 4 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:46:59 PM | 5 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:47:25 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:47:25 PM | 3 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:47:25 PM | 3 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 11 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 40 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 10 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 2 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 10 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 45 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 24 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 40 | 1367.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 13 | 1367.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:48:05 PM | 10 | 1367.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:48:11 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:11 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:11 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:11 PM | 4 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:11 PM | 36 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:11 PM | 5 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:14 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:14 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:14 PM | 4 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:14 PM | 36 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:14 PM | 4 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:23 PM | 3 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:23 PM | 7 | 1367.00 | XCSE |
46
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:48:23 PM | 12 | 1367.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:48:23 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:23 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:24 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:24 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:24 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:24 PM | 7 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:24 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:25 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:26 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:26 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:26 PM | 41 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:26 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:26 PM | 4 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:26 PM | 5 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:27 PM | 12 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:28 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:28 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:28 PM | 1 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:28 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 70 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 8 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 36 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 25 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 4 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 63 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 5 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 12 | 1366.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:48:29 PM | 11 | 1366.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:49:26 PM | 2 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:49:38 PM | 27 | 1366.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:49:40 PM | 29 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:49:40 PM | 25 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:49:44 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:49:44 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:49:44 PM | 10 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:49:44 PM | 10 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:49:44 PM | 1 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:50:14 PM | 2 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 21 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 16 | 1365.00 | XCSE |
47
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 2 | 1365.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 55 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 5 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 59 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 34 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 10 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 42 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 45 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 65 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:50:50 PM | 24 | 1364.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:51:52 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:51:52 PM | 2 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:51:52 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:51:52 PM | 41 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:04 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:04 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:04 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:04 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:04 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:05 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:05 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:05 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:05 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:07 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:07 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:08 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:08 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:14 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:14 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:14 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:15 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:15 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:21 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:21 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:24 PM | 4 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:52:49 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:53:32 PM | 74 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:53:32 PM | 9 | 1366.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:53:32 PM | 23 | 1366.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 3:53:32 PM | 43 | 1366.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 3:53:59 PM | 36 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:06 PM | 9 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:06 PM | 94 | 1367.00 | XCSE |
48
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:54:06 PM | 34 | 1367.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:54:06 PM | 9 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:06 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:07 PM | 94 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:07 PM | 94 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:07 PM | 94 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:08 PM | 38 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:08 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:08 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:08 PM | 14 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:08 PM | 94 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:08 PM | 36 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:08 PM | 5 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:08 PM | 23 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:09 PM | 4 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:09 PM | 4 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:14 PM | 8 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:14 PM | 65 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:14 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:54:14 PM | 36 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:14 PM | 2 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:26 PM | 4 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:26 PM | 30 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:54:26 PM | 23 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:55:26 PM | 10 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:55:30 PM | 36 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:55:40 PM | 22 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:55:45 PM | 66 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:56:03 PM | 13 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:56:13 PM | 32 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:56:14 PM | 4 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:56:14 PM | 5 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:56:21 PM | 2 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:56:21 PM | 71 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:56:25 PM | 2 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:25 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:25 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:25 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:26 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:26 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:27 PM | 20 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:27 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:27 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:27 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:27 PM | 12 | 1366.00 | XCSE |
49
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 3:56:34 PM | 10 | 1366.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 3:56:34 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:56:34 PM | 1 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:58:05 PM | 12 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:58:05 PM | 8 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:58:05 PM | 10 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:58:05 PM | 12 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:58:06 PM | 10 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:58:09 PM | 59 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:58:34 PM | 45 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:59:12 PM | 34 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:59:59 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:59:59 PM | 49 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:59:59 PM | 11 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 3:59:59 PM | 9 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:59:59 PM | 24 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:59:59 PM | 27 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 3:59:59 PM | 6 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:00:00 PM | 10 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:00:00 PM | 10 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:00:03 PM | 65 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:00:03 PM | 2 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:00:03 PM | 16 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:00:03 PM | 58 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:00:04 PM | 30 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:00:05 PM | 1 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:00:05 PM | 1 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:00:09 PM | 18 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:01:00 PM | 71 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:01:01 PM | 65 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:01:01 PM | 12 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:01:01 PM | 17 | 1368.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:01:01 PM | 13 | 1368.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:01:25 PM | 32 | 1368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:01:26 PM | 23 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:01:28 PM | 12 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:01:28 PM | 10 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:01:28 PM | 9 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:01 PM | 2 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:01 PM | 24 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:01 PM | 39 | 1369.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:02:01 PM | 34 | 1369.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:02:01 PM | 41 | 1369.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:02:01 PM | 34 | 1369.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:02:12 PM | 30 | 1369.00 | XCSE |
50
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:02:12 PM | 41 | 1368.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:02:12 PM | 39 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:12 PM | 25 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:12 PM | 34 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:34 PM | 58 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:34 PM | 10 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:34 PM | 26 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:34 PM | 23 | 1368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:02:36 PM | 11 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:02:36 PM | 12 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:03:13 PM | 26 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:03:13 PM | 12 | 1369.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:03:13 PM | 72 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:03:26 PM | 29 | 1368.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:03:27 PM | 2 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:03:41 PM | 50 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:03:41 PM | 22 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:03:41 PM | 50 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:03:41 PM | 1 | 1368.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:03:41 PM | 73 | 1368.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:03:41 PM | 15 | 1368.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:03:41 PM | 21 | 1368.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:03:41 PM | 30 | 1368.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:03:56 PM | 1 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:03:56 PM | 69 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:03:56 PM | 22 | 1367.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:03:56 PM | 33 | 1367.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:03:57 PM | 9 | 1367.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:04:05 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:05 PM | 64 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:05 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:05 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:06 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:06 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:06 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:06 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:06 PM | 1 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:04:06 PM | 1 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:04:07 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:07 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:07 PM | 75 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:07 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:07 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:07 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:07 PM | 10 | 1367.00 | XCSE |
51
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:04:07 PM | 34 | 1366.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 25 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 34 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 25 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:08 PM | 15 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:09 PM | 52 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:09 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:09 PM | 19 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:09 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:15 PM | 7 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:15 PM | 65 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:15 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:15 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:04:22 PM | 1 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:04:22 PM | 35 | 1366.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:05:26 PM | 10 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:05:26 PM | 49 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:06:21 PM | 34 | 1368.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:06:26 PM | 24 | 1368.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:06:26 PM | 30 | 1368.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:06:48 PM | 10 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:06:48 PM | 2 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:06:48 PM | 11 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:06:48 PM | 37 | 1368.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:07:03 PM | 47 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:07:03 PM | 25 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:07:03 PM | 42 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:07:03 PM | 27 | 1367.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:07:03 PM | 15 | 1367.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:07:25 PM | 4 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:08:13 PM | 2 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:08:13 PM | 23 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:08:15 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:08:15 PM | 2 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:08:15 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:08:15 PM | 36 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:08:20 PM | 3 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:08:29 PM | 23 | 1367.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:08:31 PM | 11 | 1367.50 | XCSE |
52
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:08:31 PM | 12 | 1367.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:08:31 PM | 36 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:08:31 PM | 4 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:09:26 PM | 74 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:09:26 PM | 2 | 1367.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:09:26 PM | 75 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:09:26 PM | 52 | 1367.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:09:26 PM | 27 | 1367.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:10:24 PM | 1 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:10:25 PM | 1 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:10:30 PM | 1 | 1367.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:10:30 PM | 6 | 1367.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:10:30 PM | 27 | 1367.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:10:47 PM | 36 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:10:47 PM | 29 | 1367.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:10:47 PM | 40 | 1367.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:10:51 PM | 1 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:10:56 PM | 34 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:10:56 PM | 8 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:10:56 PM | 26 | 1366.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:10:56 PM | 9 | 1366.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:11:37 PM | 54 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:11:37 PM | 11 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:11:38 PM | 3 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:11:38 PM | 25 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:11:38 PM | 7 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 1 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 50 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 8 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 48 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 6 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:12 PM | 44 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:13 PM | 1 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:13 PM | 48 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:13 PM | 3 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:13 PM | 9 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:13 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:13 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:13 PM | 3 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:13 PM | 9 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:15 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:15 PM | 10 | 1366.00 | XCSE |
53
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:12:18 PM | 11 | 1366.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:12:18 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:12:18 PM | 2 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:12:18 PM | 12 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:12:18 PM | 33 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:12:18 PM | 6 | 1366.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:13:05 PM | 41 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:13:05 PM | 34 | 1365.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:13:11 PM | 24 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:11 PM | 22 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:11 PM | 48 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:12 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:12 PM | 1 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:12 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:12 PM | 5 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:12 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:12 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:12 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:12 PM | 30 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:13 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:13 PM | 3 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:13 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:14 PM | 3 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:14 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:14 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:14 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:14 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:14 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:14 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:16 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:16 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:16 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:16 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:18 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:19 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:22 PM | 75 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:22 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:22 PM | 32 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:22 PM | 50 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:23 PM | 34 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:23 PM | 31 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:23 PM | 23 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:23 PM | 18 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:23 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:23 PM | 10 | 1365.50 | XCSE |
54
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:13:23 PM | 36 | 1365.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:13:26 PM | 1 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:26 PM | 42 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:26 PM | 35 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:26 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:26 PM | 23 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:26 PM | 35 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:26 PM | 11 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:26 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:27 PM | 10 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:27 PM | 10 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:35 PM | 2 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:35 PM | 17 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:13:44 PM | 27 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:13:44 PM | 20 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:13:45 PM | 10 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:14:26 PM | 2 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:14:26 PM | 29 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:14:31 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:14:31 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:14:33 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:14:33 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:01 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:01 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:03 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:03 PM | 2 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:03 PM | 7 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:04 PM | 9 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:11 PM | 1 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:11 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:12 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:12 PM | 48 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:12 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:16 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:16 PM | 48 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:19 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:23 PM | 23 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:24 PM | 1 | 1365.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:24 PM | 20 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:24 PM | 51 | 1365.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:24 PM | 73 | 1365.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:15:24 PM | 1 | 1365.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:15:24 PM | 7 | 1365.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:15:25 PM | 8 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:15:25 PM | 10 | 1364.00 | CEUX |
55
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:15:25 PM | 10 | 1364.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:15:25 PM | 2 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:15:25 PM | 6 | 1365.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:15:25 PM | 9 | 1365.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:16:10 PM | 61 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:16:10 PM | 10 | 1364.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:16:10 PM | 50 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:16:10 PM | 34 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:16:10 PM | 10 | 1364.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:16:14 PM | 7 | 1364.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:16:26 PM | 5 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:16:39 PM | 73 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:16:39 PM | 37 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:16:39 PM | 34 | 1364.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:16:39 PM | 26 | 1364.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:16:55 PM | 48 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:16:55 PM | 11 | 1364.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:17:12 PM | 71 | 1363.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:17:12 PM | 68 | 1363.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:17:12 PM | 25 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:17:12 PM | 31 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:17:12 PM | 7 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:17:12 PM | 10 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:17:12 PM | 41 | 1363.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:17:24 PM | 27 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:17:24 PM | 32 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:17:24 PM | 8 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:17:24 PM | 2 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:17:30 PM | 2 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:17:30 PM | 26 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:17:30 PM | 10 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:17:30 PM | 26 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:18:05 PM | 33 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:05 PM | 47 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 16 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 27 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 20 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 39 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 12 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 14 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 50 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 2 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 69 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:18:25 PM | 28 | 1360.00 | CEUX |
56
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:18:26 PM | 23 | 1359.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:18:26 PM | 24 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:19:33 PM | 25 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:19:52 PM | 9 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:19:52 PM | 14 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:20:05 PM | 48 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:20:05 PM | 3 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:20:05 PM | 43 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:20:35 PM | 2 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:20:35 PM | 48 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:20:35 PM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:20:50 PM | 1 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:21:25 PM | 3 | 1359.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:21:30 PM | 7 | 1359.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:22:16 PM | 41 | 1360.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:22:40 PM | 71 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:22:40 PM | 72 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:22:41 PM | 26 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:22:41 PM | 48 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:22:55 PM | 36 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:22:55 PM | 36 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:22:55 PM | 10 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:22:56 PM | 50 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:23:11 PM | 4 | 1360.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:23:55 PM | 23 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:23:55 PM | 10 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:23:56 PM | 2 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:23:56 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:23:56 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:24:32 PM | 9 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:24:32 PM | 85 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:24:38 PM | 5 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:24:57 PM | 74 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:24:57 PM | 36 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:24:57 PM | 27 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:24:57 PM | 1 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:24:57 PM | 1 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:24:57 PM | 27 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:25:04 PM | 7 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:25:04 PM | 17 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:25:09 PM | 48 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:25:09 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:25:09 PM | 32 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:25:09 PM | 73 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:25:09 PM | 10 | 1361.50 | AQEU |
57
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:25:09 PM | 15 | 1361.50 | AQEU |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:25:39 PM | 14 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:25:39 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:25:40 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:26:25 PM | 7 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:26:25 PM | 3 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:26:25 PM | 35 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:26:25 PM | 32 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:27:21 PM | 72 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:32 PM | 10 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 28 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 48 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 8 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 3 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 16 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 50 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 1 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 50 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 21 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 72 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 2 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 4 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 23 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 2 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 13 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:27:34 PM | 27 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:27:58 PM | 30 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:58 PM | 43 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:27:58 PM | 8 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:28:00 PM | 7 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:28:00 PM | 19 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:28:26 PM | 44 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:28:32 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 10 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 39 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 10 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 24 | 1359.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 12 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 48 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 12 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 12 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 45 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 39 | 1359.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:29:04 PM | 1 | 1358.50 | CEUX |
58
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:29:05 PM | 16 | 1359.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:29:05 PM | 12 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:05 PM | 45 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:05 PM | 9 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:05 PM | 12 | 1359.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:07 PM | 18 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:07 PM | 53 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:29:26 PM | 2 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:06 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:06 PM | 6 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:06 PM | 2 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:06 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:06 PM | 14 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:06 PM | 48 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 8 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 2 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 36 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 1 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 50 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 34 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 1 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 1 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 40 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 8 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:07 PM | 38 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:30:08 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:08 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:08 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:23 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:23 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:23 PM | 37 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:23 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:23 PM | 35 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:23 PM | 2 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:23 PM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:25 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:25 PM | 11 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:35 PM | 11 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:35 PM | 12 | 1360.50 | XCSE |
59
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:30:45 PM | 10 | 1360.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:30:45 PM | 11 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:45 PM | 36 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:30:59 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:30:59 PM | 70 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:31:05 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:31:05 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:31:05 PM | 25 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:31:05 PM | 48 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:31:08 PM | 25 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:31:11 PM | 16 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:31:37 PM | 15 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:31:44 PM | 1 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:31:44 PM | 5 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:32:24 PM | 38 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:32:24 PM | 1 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:32:25 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:33:23 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:23 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:23 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:23 PM | 46 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:23 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:23 PM | 34 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:23 PM | 4 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:24 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:24 PM | 23 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:24 PM | 48 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:24 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:25 PM | 48 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:33:25 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:34:08 PM | 9 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:34:08 PM | 25 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:34:14 PM | 32 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:34:14 PM | 38 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:34:14 PM | 34 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:36:16 PM | 75 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:36:16 PM | 28 | 1362.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:36:16 PM | 33 | 1362.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:36:26 PM | 22 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:26 PM | 1 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:26 PM | 48 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:26 PM | 23 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:27 PM | 23 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:27 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:27 PM | 12 | 1362.50 | XCSE |
60
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:36:27 PM | 48 | 1362.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:36:29 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:29 PM | 16 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:29 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:31 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:31 PM | 13 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:31 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:32 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:32 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:32 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:32 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:36 PM | 35 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:36 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:36 PM | 48 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:36 PM | 7 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:36 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:36 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:36 PM | 30 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:36 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 31 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 41 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 40 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 3 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:37 PM | 30 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:38 PM | 45 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:38 PM | 11 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:38 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:36:38 PM | 26 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:05 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:05 PM | 9 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:05 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:05 PM | 30 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:05 PM | 26 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:18 PM | 2 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:18 PM | 10 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:18 PM | 38 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:37:25 PM | 10 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:37:26 PM | 22 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:37:27 PM | 53 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:37:27 PM | 28 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:37:27 PM | 28 | 1362.00 | CEUX |
61
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:38:12 PM | 30 | 1362.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:38:26 PM | 2 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:38:26 PM | 43 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:38:29 PM | 22 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:38:54 PM | 38 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:38:54 PM | 9 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:39:09 PM | 38 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:39:18 PM | 12 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:39:24 PM | 11 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:39:24 PM | 38 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:39:25 PM | 74 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:39:25 PM | 75 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:39:26 PM | 3 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:39:26 PM | 27 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:39:26 PM | 38 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:39:26 PM | 11 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:40:27 PM | 3 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:40:27 PM | 7 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:40:27 PM | 23 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:40:27 PM | 42 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:40:27 PM | 3 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:40:27 PM | 39 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:40:27 PM | 38 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:40:27 PM | 27 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:40:28 PM | 25 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:40:28 PM | 49 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:41:11 PM | 1 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:11 PM | 27 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:22 PM | 17 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:41:25 PM | 22 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:41:25 PM | 26 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 48 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 47 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 1 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 25 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:35 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:36 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:36 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:36 PM | 48 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:36 PM | 11 | 1361.50 | XCSE |
62
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:41:36 PM | 12 | 1361.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:41:37 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:37 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:40 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:40 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:41 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:42 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:42 PM | 24 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:42 PM | 48 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:42 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:44 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:41:57 PM | 39 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:42:25 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:42:35 PM | 20 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:43:26 PM | 41 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:43:26 PM | 2 | 1362.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:43:26 PM | 19 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:44:27 PM | 7 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:44:29 PM | 18 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:44:44 PM | 9 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:45:04 PM | 38 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:45:04 PM | 12 | 1362.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:45:19 PM | 26 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 28 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 46 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 1 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 70 | 1362.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 72 | 1362.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 38 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 3 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 12 | 1362.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 2 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 8 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 15 | 1362.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 2 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 2 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 6 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 23 | 1362.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 2 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:46:35 PM | 22 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:46:36 PM | 2 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:46:38 PM | 29 | 1362.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:47:16 PM | 46 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:47:36 PM | 2 | 1362.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:47:36 PM | 12 | 1362.00 | AQEU |
63
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:47:36 PM | 2 | 1362.00 | AQEU |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:47:40 PM | 4 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:47:40 PM | 5 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:47:41 PM | 23 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:47:41 PM | 28 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:47:41 PM | 5 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:47:41 PM | 5 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:04 PM | 33 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:04 PM | 38 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:04 PM | 2 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:48:04 PM | 2 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:48:04 PM | 12 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:48:04 PM | 2 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:04 PM | 2 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:05 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:05 PM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:09 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:09 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:09 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:09 PM | 2 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:09 PM | 2 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 21 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 12 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 2 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 7 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 2 | 1361.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 2 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 2 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:27 PM | 11 | 1361.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:29 PM | 12 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:29 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:36 PM | 5 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:37 PM | 4 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:43 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:43 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:43 PM | 4 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:43 PM | 92 | 1361.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:43 PM | 9 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:43 PM | 16 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 9 | 1361.00 | XCSE |
64
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 42 | 1361.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 34 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 48 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 6 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 39 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 29 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 4 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 5 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 38 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:44 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 10 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 2 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 12 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 38 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:45 PM | 12 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:48:46 PM | 41 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:49:05 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:49:05 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:49:05 PM | 38 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:49:11 PM | 61 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:49:11 PM | 8 | 1360.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:49:11 PM | 25 | 1360.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:49:25 PM | 57 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:49:40 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:49:40 PM | 11 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:49:41 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:49:41 PM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:01 PM | 10 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:01 PM | 5 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:01 PM | 5 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:01 PM | 2 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:50:01 PM | 2 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:50:02 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:02 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 4 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 1 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 3 | 1360.00 | XCSE |
65
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 12 | 1360.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 11 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 4 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 9 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:11 PM | 4 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:12 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:12 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:12 PM | 11 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:12 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:12 PM | 4 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:12 PM | 9 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:12 PM | 4 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:12 PM | 5 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:13 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:15 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:15 PM | 4 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:17 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:17 PM | 39 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:18 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:18 PM | 11 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:19 PM | 11 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:19 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:19 PM | 39 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:20 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:20 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:20 PM | 4 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:20 PM | 4 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:20 PM | 5 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:21 PM | 2 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:50:22 PM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:22 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:22 PM | 11 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 12 | 1360.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 10 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 5 | 1360.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 8 | 1360.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 12 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 7 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 2 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:50:23 PM | 2 | 1360.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:51:03 PM | 62 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:51:03 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:51:07 PM | 74 | 1361.00 | CEUX |
66
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:51:24 PM | 27 | 1361.00 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:51:25 PM | 55 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:51:41 PM | 70 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:51:41 PM | 71 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:51:41 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:51:41 PM | 29 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 3 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 23 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 48 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 6 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 2 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 11 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:52:00 PM | 12 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:52:03 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:06 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:06 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:06 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:52:06 PM | 2 | 1361.00 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:52:13 PM | 4 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:52:13 PM | 2 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:52:27 PM | 26 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:53:11 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:11 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:11 PM | 3 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:11 PM | 48 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:11 PM | 94 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:11 PM | 3 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:11 PM | 6 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:12 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:12 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:12 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:12 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:12 PM | 48 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:42 PM | 10 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:53:55 PM | 22 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:53:57 PM | 12 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:57 PM | 24 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:57 PM | 11 | 1360.50 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:57 PM | 5 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:53:57 PM | 5 | 1360.50 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:53:57 PM | 2 | 1360.50 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:53:57 PM | 20 | 1360.50 | AQEU |
67
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 26-Mar-25 | 4:53:57 PM | 2 | 1360.50 | AQEU |
|---|---|---|---|---|---|
| GENMAB A/S | 26-Mar-25 | 4:53:58 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:58 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:58 PM | 11 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:53:58 PM | 35 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:53:58 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:53:58 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:53:58 PM | 15 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:53:58 PM | 4 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:54:05 PM | 75 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:54:05 PM | 75 | 1361.00 | CEUX |
| GENMAB A/S | 26-Mar-25 | 4:54:10 PM | 42 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:54:10 PM | 33 | 1361.00 | TQEX |
| GENMAB A/S | 26-Mar-25 | 4:54:29 PM | 10 | 1360.50 | AQEU |
| GENMAB A/S | 26-Mar-25 | 4:54:32 PM | 75 | 1361.00 | XCSE |
| GENMAB A/S | 26-Mar-25 | 4:54:37 PM | 25 | 1361.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:42:33 AM | 49 | 1344.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:43:04 AM | 69 | 1345.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 9:43:31 AM | 24 | 1344.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:43:32 AM | 70 | 1344.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 9:43:36 AM | 70 | 1343.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:43:36 AM | 64 | 1343.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:43:36 AM | 65 | 1343.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 9:44:02 AM | 3 | 1344.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:44:02 AM | 18 | 1344.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:44:02 AM | 11 | 1344.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:44:02 AM | 23 | 1344.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:44:02 AM | 22 | 1344.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 9:44:02 AM | 24 | 1344.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 9:44:39 AM | 8 | 1343.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:45:08 AM | 16 | 1343.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:45:08 AM | 51 | 1343.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:45:08 AM | 14 | 1343.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 9:45:08 AM | 45 | 1343.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 9:45:32 AM | 31 | 1342.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:45:32 AM | 75 | 1342.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 9:45:51 AM | 28 | 1342.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:45:51 AM | 44 | 1342.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:48:05 AM | 2 | 1342.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:49:12 AM | 12 | 1343.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:49:20 AM | 46 | 1343.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:51:12 AM | 57 | 1343.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:51:12 AM | 20 | 1343.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:52:29 AM | 75 | 1343.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 9:52:29 AM | 35 | 1343.50 | TQEX |
68
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 9:53:16 AM | 74 | 1343.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 9:53:16 AM | 11 | 1343.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:53:16 AM | 18 | 1343.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:54:42 AM | 46 | 1343.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:55:22 AM | 10 | 1343.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:59:07 AM | 32 | 1345.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:59:56 AM | 44 | 1345.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 9:59:56 AM | 29 | 1345.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:01:04 AM | 73 | 1344.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:01:04 AM | 1 | 1344.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:04:06 AM | 13 | 1344.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:05:26 AM | 74 | 1344.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:06:35 AM | 1 | 1345.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:07:01 AM | 66 | 1345.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:07:01 AM | 9 | 1345.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:29 AM | 33 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:29 AM | 2 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:29 AM | 43 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:29 AM | 9 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:29 AM | 9 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:41 AM | 17 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:41 AM | 16 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:41 AM | 57 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:09:41 AM | 8 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:10:00 AM | 26 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:10:00 AM | 12 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:10:00 AM | 6 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:10:01 AM | 10 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:10:45 AM | 72 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:10:45 AM | 73 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:12:02 AM | 15 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:12:02 AM | 3 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:12:02 AM | 75 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:12:03 AM | 16 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:12:10 AM | 10 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:12:10 AM | 4 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:12:10 AM | 9 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:12:10 AM | 10 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:12:13 AM | 15 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:14:00 AM | 16 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:14:00 AM | 15 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:14:00 AM | 38 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:14:00 AM | 4 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:14:00 AM | 21 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:14:00 AM | 36 | 1347.00 | CEUX |
69
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 10:15:01 AM | 51 | 1346.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 10:15:01 AM | 36 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:01 AM | 72 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:01 AM | 11 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:01 AM | 6 | 1346.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:15:01 AM | 36 | 1346.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:15:01 AM | 71 | 1346.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:15:02 AM | 30 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:02 AM | 11 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:02 AM | 49 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:02 AM | 8 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:04 AM | 15 | 1346.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:04 AM | 7 | 1346.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:10 AM | 19 | 1345.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:10 AM | 59 | 1345.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:15:10 AM | 20 | 1345.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:15:19 AM | 36 | 1345.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:17:03 AM | 7 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:20:08 AM | 15 | 1347.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:20:28 AM | 7 | 1347.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:21:45 AM | 11 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:21:45 AM | 5 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:21:45 AM | 9 | 1347.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:21:45 AM | 36 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:21:45 AM | 5 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:21:46 AM | 13 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:21:46 AM | 30 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:21:46 AM | 20 | 1347.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:22:53 AM | 73 | 1346.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:22:53 AM | 6 | 1346.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:24:43 AM | 5 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:24:43 AM | 5 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:24:43 AM | 18 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:24:43 AM | 5 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:25:04 AM | 11 | 1347.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:27:16 AM | 19 | 1349.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:27:16 AM | 12 | 1349.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:27:16 AM | 33 | 1349.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:27:16 AM | 1 | 1349.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:27:16 AM | 12 | 1349.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:29:47 AM | 98 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:29:47 AM | 46 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:29:47 AM | 39 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:29:47 AM | 13 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:29:47 AM | 7 | 1350.00 | CEUX |
70
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 10:29:47 AM | 12 | 1350.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 10:30:18 AM | 37 | 1349.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:30:18 AM | 4 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:30:18 AM | 43 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:30:18 AM | 9 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:30:18 AM | 43 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:30:18 AM | 18 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:30:18 AM | 36 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:31:53 AM | 11 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:31:53 AM | 3 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:31:53 AM | 9 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:32:03 AM | 3 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:32:24 AM | 10 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:32:24 AM | 4 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:32:24 AM | 6 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:32:28 AM | 26 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:32:28 AM | 11 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:33:06 AM | 34 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:34:10 AM | 3 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:34:10 AM | 21 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:34:10 AM | 3 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:34:11 AM | 28 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:34:12 AM | 77 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:34:12 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:34:12 AM | 57 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:34:12 AM | 10 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:34:12 AM | 42 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:34:13 AM | 22 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:34:13 AM | 16 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:34:21 AM | 15 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:35:03 AM | 11 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:35:07 AM | 28 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:35:24 AM | 16 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:35:26 AM | 36 | 1351.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:35:27 AM | 64 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:35:27 AM | 10 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:38:23 AM | 72 | 1350.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:38:23 AM | 72 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:38:23 AM | 31 | 1350.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:38:23 AM | 1 | 1350.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:38:23 AM | 36 | 1350.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:38:23 AM | 37 | 1350.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:38:25 AM | 54 | 1349.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:38:25 AM | 19 | 1349.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:38:25 AM | 25 | 1350.00 | XCSE |
71
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 10:38:25 AM | 4 | 1350.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 10:38:25 AM | 5 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:38:25 AM | 12 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:38:25 AM | 4 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:38:25 AM | 23 | 1349.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:38:52 AM | 10 | 1349.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:41:39 AM | 29 | 1350.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:42:14 AM | 75 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:42:14 AM | 28 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:42:14 AM | 46 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:42:14 AM | 25 | 1350.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 10:42:16 AM | 10 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:42:16 AM | 15 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:42:16 AM | 13 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:42:16 AM | 19 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:42:18 AM | 1 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:42:24 AM | 12 | 1350.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:45:19 AM | 8 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 66 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 13 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 48 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 4 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 72 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 5 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 30 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 5 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 34 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 39 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 31 | 1351.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:45:59 AM | 22 | 1351.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 10:46:00 AM | 36 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:00 AM | 5 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:00 AM | 4 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:00 AM | 4 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:01 AM | 31 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:01 AM | 31 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:06 AM | 22 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:07 AM | 12 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:07 AM | 5 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:07 AM | 4 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:07 AM | 5 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:07 AM | 14 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:07 AM | 17 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:07 AM | 2 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:09 AM | 3 | 1351.00 | CEUX |
72
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 10:46:14 AM | 13 | 1351.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 10:46:42 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:46:42 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:46:42 AM | 10 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:46:42 AM | 5 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:42 AM | 4 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:46:42 AM | 4 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:49:33 AM | 50 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:50:21 AM | 30 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:50:21 AM | 19 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:50:21 AM | 13 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:51:40 AM | 18 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:51:40 AM | 2 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:51:41 AM | 25 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:51:43 AM | 15 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:51:44 AM | 22 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:51:45 AM | 4 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:51:48 AM | 14 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:55:17 AM | 76 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:55:17 AM | 77 | 1350.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:55:17 AM | 77 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:55:17 AM | 30 | 1350.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:55:17 AM | 23 | 1351.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 10:55:40 AM | 50 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:55:40 AM | 5 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:55:40 AM | 73 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:55:40 AM | 18 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:55:40 AM | 25 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:55:40 AM | 19 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:56:11 AM | 22 | 1352.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 10 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 20 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 50 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 20 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 10 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:12 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:26 AM | 78 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:26 AM | 8 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:26 AM | 43 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:26 AM | 26 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:26 AM | 5 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:26 AM | 8 | 1352.00 | XCSE |
73
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 10:56:26 AM | 8 | 1352.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 10:56:26 AM | 15 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:56:27 AM | 10 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:27 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:56:27 AM | 9 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 3 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 30 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 6 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 2 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 11 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:00 AM | 3 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:01 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:01 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:01 AM | 43 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:01 AM | 2 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:01 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:01 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:01 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:01 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:02 AM | 43 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:02 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:02 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 10:58:04 AM | 14 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:58:04 AM | 5 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:58:04 AM | 10 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:59:52 AM | 15 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:59:53 AM | 14 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 10:59:55 AM | 2 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:00:13 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:00:13 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:00:13 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:00:21 AM | 10 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:01:06 AM | 11 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:01:51 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:01:51 AM | 11 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:01:57 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:14 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:14 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:14 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:14 AM | 5 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:15 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:15 AM | 10 | 1352.50 | XCSE |
74
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:02:15 AM | 10 | 1352.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:02:36 AM | 11 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:50 AM | 45 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:50 AM | 5 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:51 AM | 45 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:51 AM | 45 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:51 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:51 AM | 5 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:51 AM | 4 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:51 AM | 4 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:51 AM | 5 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:51 AM | 4 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:56 AM | 54 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:56 AM | 44 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:02:56 AM | 7 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:56 AM | 73 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:02:56 AM | 29 | 1352.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:03:27 AM | 39 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:38 AM | 2 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:38 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:38 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:38 AM | 29 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:38 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:38 AM | 2 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:38 AM | 36 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:39 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:39 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:39 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:39 AM | 3 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:40 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:40 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:40 AM | 8 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:43 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:44 AM | 4 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:44 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:44 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:46 AM | 9 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:46 AM | 10 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:04:46 AM | 3 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:05:42 AM | 30 | 1352.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:05:45 AM | 41 | 1352.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:05:45 AM | 17 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:05:45 AM | 23 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:05:45 AM | 26 | 1352.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:07:10 AM | 5 | 1352.00 | CEUX |
75
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:07:10 AM | 72 | 1352.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:07:10 AM | 5 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:07:10 AM | 4 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:07:10 AM | 32 | 1352.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:07:11 AM | 32 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:07:11 AM | 29 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:07:11 AM | 19 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:07:13 AM | 36 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:07:13 AM | 22 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:53 AM | 24 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:53 AM | 4 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:53 AM | 11 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:53 AM | 5 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:53 AM | 11 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:53 AM | 13 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:55 AM | 30 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:55 AM | 10 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:55 AM | 9 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:55 AM | 10 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:55 AM | 8 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:55 AM | 8 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 7 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 32 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 10 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 10 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 10 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 11 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 9 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 3 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 8 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 17 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 43 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 6 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:56 AM | 30 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:58 AM | 40 | 1353.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:58 AM | 74 | 1352.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:09:58 AM | 20 | 1352.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:58 AM | 74 | 1353.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:09:58 AM | 22 | 1353.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:10:14 AM | 75 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:10:14 AM | 73 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:10:14 AM | 78 | 1351.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:10:14 AM | 24 | 1351.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:10:14 AM | 26 | 1352.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:10:14 AM | 24 | 1352.00 | AQEU |
76
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:10:42 AM | 38 | 1350.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:10:42 AM | 73 | 1350.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:12:17 AM | 2 | 1352.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:13:07 AM | 37 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:13:16 AM | 38 | 1351.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:13:16 AM | 75 | 1351.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:13:16 AM | 36 | 1352.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:13:16 AM | 32 | 1352.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:13:34 AM | 26 | 1351.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:13:35 AM | 14 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:13:35 AM | 33 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:13:35 AM | 8 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:13:35 AM | 43 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:13:35 AM | 37 | 1350.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:13:35 AM | 36 | 1350.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:15:11 AM | 76 | 1350.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:11 AM | 11 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:11 AM | 57 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:11 AM | 30 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:11 AM | 1 | 1350.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:15:12 AM | 10 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:12 AM | 23 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:12 AM | 8 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:12 AM | 10 | 1351.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:19 AM | 75 | 1350.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:26 AM | 43 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:26 AM | 77 | 1357.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:26 AM | 23 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:26 AM | 11 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:26 AM | 76 | 1356.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:15:31 AM | 43 | 1356.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:31 AM | 22 | 1356.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:31 AM | 33 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:31 AM | 36 | 1356.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:15:41 AM | 20 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:41 AM | 74 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:41 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:41 AM | 22 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:15:41 AM | 76 | 1355.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:15:41 AM | 74 | 1355.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:16:06 AM | 74 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:16:06 AM | 12 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:16:06 AM | 71 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:16:06 AM | 36 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:16:06 AM | 73 | 1355.00 | CEUX |
77
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:16:06 AM | 68 | 1354.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:16:06 AM | 71 | 1354.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:16:07 AM | 36 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:16:48 AM | 19 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:16:48 AM | 28 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:16:48 AM | 26 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:16:48 AM | 2 | 1354.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:16:51 AM | 16 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:16:51 AM | 8 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:17:57 AM | 27 | 1354.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:18:00 AM | 30 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:18:00 AM | 17 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:18:00 AM | 36 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:18:00 AM | 22 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:18:00 AM | 18 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:18:00 AM | 63 | 1354.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:18:00 AM | 28 | 1354.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:18:00 AM | 14 | 1354.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:18:02 AM | 31 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:18:04 AM | 36 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:18:10 AM | 24 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:18:13 AM | 58 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:18:13 AM | 30 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:18:13 AM | 17 | 1353.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:18:13 AM | 60 | 1353.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:18:52 AM | 41 | 1353.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:20:00 AM | 11 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:00 AM | 87 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:01 AM | 11 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:01 AM | 2 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:01 AM | 1 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:01 AM | 3 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:01 AM | 1 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:09 AM | 46 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:09 AM | 23 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:09 AM | 7 | 1353.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:20:09 AM | 14 | 1353.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:20:09 AM | 15 | 1353.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:20:14 AM | 17 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:38 AM | 3 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:38 AM | 19 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:20:38 AM | 3 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:21:42 AM | 2 | 1353.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:22:12 AM | 12 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:22:12 AM | 12 | 1354.00 | CEUX |
78
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:22:12 AM | 24 | 1354.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:22:12 AM | 9 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:24:07 AM | 17 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:24:10 AM | 18 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:24:11 AM | 30 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:24:11 AM | 30 | 1354.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:24:11 AM | 40 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:24:11 AM | 2 | 1354.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:25:16 AM | 32 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:16 AM | 15 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:16 AM | 15 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:16 AM | 5 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:16 AM | 31 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 25 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 8 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 1 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 8 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 8 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 48 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 14 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 43 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 3 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:17 AM | 3 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:28 AM | 20 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:33 AM | 25 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:33 AM | 38 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:33 AM | 30 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:34 AM | 30 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:34 AM | 10 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:34 AM | 8 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:34 AM | 10 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:34 AM | 30 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:35 AM | 30 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:35 AM | 8 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:25:36 AM | 4 | 1354.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:28:06 AM | 6 | 1354.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:06 AM | 25 | 1354.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:06 AM | 10 | 1354.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:06 AM | 9 | 1354.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:06 AM | 19 | 1354.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:06 AM | 8 | 1354.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:06 AM | 10 | 1354.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:27 AM | 4 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:27 AM | 15 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:27 AM | 22 | 1355.00 | CEUX |
79
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:28:27 AM | 6 | 1355.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:28:27 AM | 8 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:28:28 AM | 32 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:29:16 AM | 74 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:29:16 AM | 60 | 1355.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:29:16 AM | 14 | 1355.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:29:17 AM | 23 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:29:17 AM | 44 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:29:17 AM | 32 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:29:17 AM | 35 | 1355.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:29:36 AM | 22 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:29:36 AM | 30 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:29:36 AM | 21 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:29:36 AM | 77 | 1354.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:33:32 AM | 15 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:33:32 AM | 4 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:33:32 AM | 23 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:33:32 AM | 9 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:33:32 AM | 10 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:33:36 AM | 14 | 1355.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:33:54 AM | 23 | 1355.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:33:58 AM | 17 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:33:58 AM | 3 | 1355.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 30 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 74 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 9 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 6 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 68 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 4 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 26 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 24 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:35:53 AM | 36 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:35:54 AM | 23 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:36:13 AM | 7 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:36:13 AM | 47 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:36:13 AM | 21 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:36:13 AM | 75 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:36:13 AM | 15 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:36:13 AM | 24 | 1355.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:36:36 AM | 3 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:36:44 AM | 2 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:17 AM | 30 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:17 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:17 AM | 9 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:17 AM | 34 | 1355.50 | XCSE |
80
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:37:17 AM | 30 | 1355.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:37:17 AM | 73 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:17 AM | 8 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:17 AM | 38 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:18 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:30 AM | 9 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:30 AM | 9 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:30 AM | 9 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:30 AM | 3 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:30 AM | 8 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:32 AM | 8 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:32 AM | 9 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:32 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:33 AM | 8 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:38 AM | 19 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:39 AM | 2 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:41 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:41 AM | 8 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:41 AM | 9 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:43 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:37:45 AM | 46 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:39:58 AM | 36 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:39:58 AM | 25 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:40:00 AM | 30 | 1355.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:40:28 AM | 13 | 1355.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:43:11 AM | 25 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:43:11 AM | 44 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:43:11 AM | 36 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:43:11 AM | 11 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:43:11 AM | 14 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:43:11 AM | 30 | 1355.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:43:11 AM | 4 | 1355.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:43:51 AM | 30 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:43:51 AM | 43 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:43:51 AM | 39 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:43:51 AM | 17 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:43:51 AM | 22 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:43:51 AM | 14 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:43:51 AM | 24 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:43:52 AM | 3 | 1355.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:44:02 AM | 50 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:03 AM | 27 | 1355.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 8 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 27 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 13 | 1355.50 | XCSE |
81
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 27 | 1355.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 9 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 27 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 19 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 4 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 28 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 21 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:44:53 AM | 4 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:44:57 AM | 2 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:57 AM | 93 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:44:58 AM | 2 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:45:06 AM | 45 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:45:06 AM | 3 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:45:06 AM | 28 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:45:07 AM | 20 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:45:07 AM | 62 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:45:29 AM | 1 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:45:29 AM | 12 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:45:29 AM | 5 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:45:59 AM | 15 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:45:59 AM | 36 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:45:59 AM | 3 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:46:31 AM | 17 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:46:31 AM | 10 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:46:31 AM | 23 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:46:37 AM | 10 | 1356.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:46:37 AM | 9 | 1356.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:46:38 AM | 8 | 1356.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:47:07 AM | 78 | 1356.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:48:09 AM | 4 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:48:09 AM | 43 | 1355.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:48:09 AM | 36 | 1356.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:48:09 AM | 5 | 1356.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:48:09 AM | 77 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:48:09 AM | 20 | 1355.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:48:09 AM | 25 | 1355.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 43 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 9 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 9 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 9 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 9 | 1356.50 | XCSE |
82
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 43 | 1356.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:49:37 AM | 28 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:38 AM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:38 AM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:38 AM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:38 AM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:38 AM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:38 AM | 12 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:38 AM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:38 AM | 41 | 1356.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:49:40 AM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:40 AM | 9 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:40 AM | 8 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:45 AM | 9 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:45 AM | 13 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:49:48 AM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:50:43 AM | 10 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:50:43 AM | 1 | 1356.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:51:24 AM | 96 | 1357.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:51:24 AM | 2 | 1357.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:51:27 AM | 3 | 1357.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:51:27 AM | 18 | 1357.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:52:04 AM | 7 | 1357.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:52:30 AM | 2 | 1358.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:52:30 AM | 50 | 1358.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:52:36 AM | 2 | 1358.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:52:51 AM | 3 | 1358.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:53:02 AM | 3 | 1358.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:53:03 AM | 13 | 1358.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:53:03 AM | 15 | 1358.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:53:31 AM | 3 | 1358.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:53:51 AM | 12 | 1358.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:55:09 AM | 73 | 1358.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:09 AM | 32 | 1358.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:55:09 AM | 43 | 1358.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:55:09 AM | 34 | 1358.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:55:42 AM | 9 | 1360.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:42 AM | 8 | 1360.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:42 AM | 10 | 1360.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:42 AM | 72 | 1360.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:55:43 AM | 75 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:43 AM | 78 | 1360.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:55:43 AM | 44 | 1360.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:55:45 AM | 70 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:45 AM | 15 | 1360.00 | XCSE |
83
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:55:45 AM | 13 | 1360.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 7 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 11 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 25 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 36 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:46 AM | 11 | 1359.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:55:47 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:47 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:47 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:47 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:47 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:47 AM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:48 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:51 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:58 AM | 4 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:58 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:58 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:58 AM | 43 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:58 AM | 24 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:58 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:58 AM | 66 | 1359.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:55:59 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:59 AM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:59 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:59 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:59 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:55:59 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:00 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:00 AM | 9 | 1360.00 | XCSE |
84
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:56:00 AM | 8 | 1360.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:56:01 AM | 10 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:01 AM | 9 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:01 AM | 8 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:56 AM | 29 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:56 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:56 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:56 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:56:56 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:57:11 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:57:44 AM | 2 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:57:51 AM | 3 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 7 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 2 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 45 | 1360.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 34 | 1360.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:58:06 AM | 43 | 1360.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 30 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 39 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 30 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 31 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 29 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:07 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:08 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:08 AM | 42 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:08 AM | 30 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:08 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:08 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:08 AM | 17 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:08 AM | 30 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 8 | 1361.00 | XCSE |
85
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 10 | 1361.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 14 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 27 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 16 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 26 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 9 | 1360.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 68 | 1360.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 11:58:09 AM | 11 | 1360.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:58:10 AM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:10 AM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:10 AM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:10 AM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:10 AM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:10 AM | 26 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:10 AM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:13 AM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:13 AM | 23 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:18 AM | 23 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:19 AM | 2 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 2 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 25 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:22 AM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:23 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:23 AM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:23 AM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:23 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:23 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:23 AM | 14 | 1361.50 | XCSE |
86
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 11:58:23 AM | 9 | 1361.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 11:58:23 AM | 1 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:24 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:24 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:58:27 AM | 71 | 1361.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 11:58:27 AM | 54 | 1361.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 33 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 31 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 16 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 13 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 7 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:47 AM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:48 AM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 11:59:48 AM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:00:13 PM | 22 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:00:13 PM | 43 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:00:24 PM | 76 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:00:24 PM | 24 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:00:24 PM | 78 | 1361.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:00:43 PM | 2 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:00:51 PM | 3 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:17 PM | 69 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:17 PM | 31 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:18 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:18 PM | 39 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:18 PM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:18 PM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:18 PM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:18 PM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:19 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:19 PM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:19 PM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:19 PM | 10 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:20 PM | 39 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:20 PM | 39 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:20 PM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:20 PM | 8 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:20 PM | 9 | 1361.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:20 PM | 9 | 1361.50 | XCSE |
87
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 12:01:20 PM | 42 | 1361.00 | AQEU |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 12:01:28 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:28 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:36 PM | 28 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:01:36 PM | 5 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:02:06 PM | 37 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:02:06 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:02:18 PM | 54 | 1360.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:02:58 PM | 78 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:02:58 PM | 72 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:02:58 PM | 60 | 1363.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:02:58 PM | 39 | 1363.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:03:21 PM | 75 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:03:21 PM | 32 | 1363.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:03:23 PM | 48 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:03:23 PM | 33 | 1363.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:03:23 PM | 18 | 1363.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:04:34 PM | 10 | 1363.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:09:49 PM | 62 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:09:50 PM | 30 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:05 PM | 14 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:20 PM | 33 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:20 PM | 34 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:20 PM | 15 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:20 PM | 13 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:20 PM | 43 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:20 PM | 16 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:20 PM | 17 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:21 PM | 9 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:21 PM | 33 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:21 PM | 98 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:21 PM | 8 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:10:21 PM | 8 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:11:06 PM | 4 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:11:06 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:11:06 PM | 4 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:11:06 PM | 8 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:11:06 PM | 9 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:11:33 PM | 74 | 1362.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:11:33 PM | 72 | 1362.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:11:33 PM | 58 | 1362.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:11:33 PM | 12 | 1362.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:11:33 PM | 3 | 1362.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:11:33 PM | 21 | 1362.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:11:42 PM | 47 | 1361.00 | XCSE |
88
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 12:11:42 PM | 25 | 1361.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 12:11:42 PM | 22 | 1361.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:11:42 PM | 30 | 1361.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:12:01 PM | 33 | 1360.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:12:07 PM | 27 | 1360.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:12:07 PM | 15 | 1360.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:12:09 PM | 9 | 1360.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:13:56 PM | 4 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:13:56 PM | 23 | 1360.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:14:12 PM | 74 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:14:12 PM | 70 | 1359.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:14:12 PM | 6 | 1359.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:14:12 PM | 28 | 1359.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:15:40 PM | 22 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:15:46 PM | 9 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:15:46 PM | 10 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:15:46 PM | 9 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:16:45 PM | 43 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:16:45 PM | 6 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:17:40 PM | 8 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:17:40 PM | 2 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:17:46 PM | 26 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:17:47 PM | 3 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:18:08 PM | 75 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:18:08 PM | 8 | 1359.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:18:15 PM | 76 | 1358.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:18:15 PM | 72 | 1358.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:18:15 PM | 24 | 1358.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:18:15 PM | 3 | 1358.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:19:27 PM | 50 | 1357.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:23:19 PM | 9 | 1358.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:23:19 PM | 43 | 1358.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:23:19 PM | 15 | 1358.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:23:19 PM | 2 | 1358.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:23:19 PM | 10 | 1358.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:23:19 PM | 13 | 1358.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:23:19 PM | 7 | 1358.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:23:24 PM | 75 | 1359.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:27:25 PM | 43 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:27:25 PM | 9 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:27:26 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:27:26 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:27:26 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:27:26 PM | 1 | 1359.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:27:27 PM | 72 | 1360.50 | XCSE |
89
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 12:27:27 PM | 5 | 1361.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 12:27:27 PM | 73 | 1360.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:27:27 PM | 5 | 1361.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:27:27 PM | 36 | 1361.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:27:27 PM | 4 | 1361.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:27:27 PM | 31 | 1360.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:30:24 PM | 28 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:24 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:24 PM | 6 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:25 PM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:25 PM | 14 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:25 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:25 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:26 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:26 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:26 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:27 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:29 PM | 2 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:29 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:29 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:31 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:32 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:32 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:32 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:32 PM | 2 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:33 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:33 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:41 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:41 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:43 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:30:43 PM | 9 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:31:17 PM | 14 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:32:35 PM | 43 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:32:35 PM | 10 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:32:37 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:32:37 PM | 13 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:32:41 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:32:42 PM | 8 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:34:36 PM | 20 | 1361.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:35:49 PM | 76 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:35:49 PM | 36 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:49 PM | 72 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:49 PM | 26 | 1363.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:35:49 PM | 8 | 1363.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:35:49 PM | 24 | 1363.00 | AQEU |
90
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 12:35:50 PM | 41 | 1363.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 12:35:50 PM | 19 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:35:50 PM | 38 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:35:50 PM | 78 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 23 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 19 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 43 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 5 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 12 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 4 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 5 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 5 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 36 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:35:51 PM | 25 | 1362.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:35:53 PM | 21 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:36:05 PM | 13 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:36:16 PM | 44 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:36:16 PM | 8 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:36:19 PM | 15 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:39:27 PM | 76 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:39:27 PM | 73 | 1363.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:41:48 PM | 73 | 1362.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:41:48 PM | 43 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:41:48 PM | 77 | 1362.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:41:48 PM | 40 | 1362.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:41:48 PM | 23 | 1362.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:41:48 PM | 22 | 1362.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:43:08 PM | 28 | 1362.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:43:08 PM | 10 | 1362.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:43:08 PM | 13 | 1362.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:43:16 PM | 10 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:43:16 PM | 43 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:43:16 PM | 77 | 1362.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:43:23 PM | 72 | 1362.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:43:35 PM | 78 | 1362.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:44:10 PM | 24 | 1361.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:44:10 PM | 22 | 1361.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:44:53 PM | 8 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:44:53 PM | 9 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:44:53 PM | 20 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:44:53 PM | 9 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:44:54 PM | 14 | 1363.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:45:02 PM | 24 | 1365.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:45:02 PM | 8 | 1365.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:45:02 PM | 43 | 1365.50 | XCSE |
91
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 12:45:02 PM | 17 | 1365.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 12:45:02 PM | 46 | 1365.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:45:02 PM | 28 | 1365.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:45:02 PM | 26 | 1365.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:45:03 PM | 41 | 1365.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:45:15 PM | 63 | 1365.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:45:15 PM | 20 | 1365.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:45:15 PM | 76 | 1365.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:45:15 PM | 15 | 1365.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:45:15 PM | 68 | 1365.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:45:15 PM | 22 | 1365.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:45:15 PM | 34 | 1365.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:47:02 PM | 22 | 1364.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:47:06 PM | 3 | 1364.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:48:18 PM | 73 | 1366.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:48:18 PM | 76 | 1366.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:48:18 PM | 23 | 1366.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:48:22 PM | 33 | 1366.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:00 PM | 1 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:01 PM | 21 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:13 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:14 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:17 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:21 PM | 9 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:21 PM | 9 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:21 PM | 4 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:50:27 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:53:43 PM | 15 | 1368.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 15 | 1366.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 27 | 1366.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 77 | 1366.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 41 | 1366.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 75 | 1368.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 73 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 98 | 1368.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 46 | 1366.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 76 | 1368.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 78 | 1367.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 1 | 1368.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 29 | 1367.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 22 | 1366.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 23 | 1368.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 22 | 1367.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:55:17 PM | 23 | 1366.00 | AQEU |
92
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 12:55:18 PM | 11 | 1365.50 | AQEU |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 12:55:21 PM | 28 | 1365.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:55:33 PM | 76 | 1364.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:33 PM | 9 | 1364.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:55:33 PM | 67 | 1364.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:55:43 PM | 78 | 1363.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:55:44 PM | 19 | 1363.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:44 PM | 55 | 1363.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:55:44 PM | 15 | 1364.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:55:44 PM | 9 | 1364.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 12:55:51 PM | 45 | 1362.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 12:55:53 PM | 76 | 1362.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:57:14 PM | 27 | 1363.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 12:59:36 PM | 48 | 1363.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 12:59:36 PM | 29 | 1363.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:00:00 PM | 48 | 1363.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:00:26 PM | 48 | 1364.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:00:26 PM | 8 | 1364.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:00:26 PM | 13 | 1364.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:00:51 PM | 39 | 1363.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:04:20 PM | 56 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:20 PM | 17 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:20 PM | 69 | 1367.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:04:20 PM | 40 | 1367.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:04:21 PM | 9 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:21 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:21 PM | 8 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:21 PM | 24 | 1367.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:04:24 PM | 62 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:24 PM | 22 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:29 PM | 36 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:56 PM | 27 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:56 PM | 5 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:56 PM | 21 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:56 PM | 25 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:56 PM | 8 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:04:56 PM | 9 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:06:18 PM | 24 | 1367.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:06:29 PM | 34 | 1367.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:08:07 PM | 22 | 1367.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:08:42 PM | 40 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:08:42 PM | 18 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:08:42 PM | 24 | 1367.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:08:43 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:08:56 PM | 26 | 1367.00 | XCSE |
93
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 1:09:09 PM | 10 | 1367.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 1:09:09 PM | 19 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:09 PM | 7 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:09 PM | 9 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:09 PM | 37 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:09 PM | 8 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:09 PM | 8 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:17 PM | 26 | 1366.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:17 PM | 50 | 1366.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:18 PM | 58 | 1366.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:09:43 PM | 2 | 1365.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:43 PM | 73 | 1365.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:09:48 PM | 36 | 1365.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:11:31 PM | 75 | 1367.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:12:13 PM | 40 | 1367.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:12:18 PM | 17 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:12:18 PM | 8 | 1367.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:12:19 PM | 25 | 1367.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:12:19 PM | 3 | 1367.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:12:25 PM | 1 | 1367.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:13:10 PM | 34 | 1368.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:13:26 PM | 16 | 1368.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:13:29 PM | 6 | 1368.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:13:30 PM | 26 | 1368.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:14:23 PM | 27 | 1371.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:14:23 PM | 2 | 1371.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:14:23 PM | 35 | 1371.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:14:24 PM | 8 | 1371.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:14:24 PM | 8 | 1371.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:14:24 PM | 11 | 1371.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:14:25 PM | 74 | 1371.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:15:05 PM | 74 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:15:08 PM | 74 | 1372.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:15:32 PM | 77 | 1372.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:15:54 PM | 72 | 1371.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:15:54 PM | 56 | 1371.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:19:02 PM | 14 | 1371.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:19:18 PM | 14 | 1371.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:19:37 PM | 6 | 1371.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:19:39 PM | 10 | 1371.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:19:39 PM | 33 | 1371.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:19:39 PM | 10 | 1371.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:19:39 PM | 10 | 1371.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:20:39 PM | 14 | 1371.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:20:39 PM | 11 | 1371.50 | XCSE |
94
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 1:20:39 PM | 50 | 1371.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 1:20:39 PM | 23 | 1371.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:21:15 PM | 18 | 1372.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:21:15 PM | 57 | 1372.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:23:06 PM | 19 | 1373.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:23:06 PM | 14 | 1373.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:23:10 PM | 44 | 1373.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:23:10 PM | 20 | 1373.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:23:10 PM | 34 | 1373.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:23:10 PM | 76 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:23:10 PM | 64 | 1373.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:23:10 PM | 42 | 1373.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:24:27 PM | 4 | 1372.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:24:35 PM | 4 | 1372.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:25:35 PM | 38 | 1372.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:25:35 PM | 68 | 1372.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:25:35 PM | 60 | 1372.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:26:00 PM | 14 | 1371.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:26:56 PM | 43 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:26:56 PM | 3 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:26:56 PM | 15 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:26:56 PM | 9 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:26:56 PM | 2 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:26:56 PM | 2 | 1372.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:26:56 PM | 24 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:28:09 PM | 42 | 1375.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:28:09 PM | 34 | 1375.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:28:09 PM | 42 | 1375.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:29:38 PM | 36 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:29:38 PM | 30 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:29:38 PM | 72 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:29:38 PM | 22 | 1375.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:30:31 PM | 19 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:30:31 PM | 11 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:30:31 PM | 22 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:30:31 PM | 46 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:33:07 PM | 73 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:33:07 PM | 26 | 1376.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:34:14 PM | 47 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:34:14 PM | 51 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:34:15 PM | 41 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:15 PM | 35 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:15 PM | 42 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:15 PM | 21 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:15 PM | 72 | 1376.50 | CEUX |
95
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 1:37:15 PM | 32 | 1376.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 1:37:15 PM | 31 | 1376.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:37:17 PM | 9 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:17 PM | 10 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:17 PM | 8 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:17 PM | 32 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:17 PM | 18 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:17 PM | 17 | 1377.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:37:37 PM | 23 | 1378.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:41:27 PM | 26 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:27 PM | 8 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:27 PM | 10 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:27 PM | 11 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:27 PM | 18 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:27 PM | 14 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:27 PM | 7 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:32 PM | 31 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:41:32 PM | 40 | 1378.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 15 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 15 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 8 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 26 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 9 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 46 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 10 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 20 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 74 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 4 | 1378.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 72 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 3 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 23 | 1377.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:41:42 PM | 22 | 1377.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:41:52 PM | 8 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:41:56 PM | 5 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:41:57 PM | 12 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:42:16 PM | 45 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:42:16 PM | 17 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:42:19 PM | 20 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:42:19 PM | 14 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:42:30 PM | 3 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:44:24 PM | 10 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:44:24 PM | 8 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:44:24 PM | 69 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:44:24 PM | 9 | 1378.50 | CEUX |
96
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 1:44:24 PM | 73 | 1378.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 1:44:24 PM | 22 | 1378.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:44:25 PM | 29 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:44:25 PM | 21 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:44:25 PM | 9 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:44:25 PM | 30 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:44:25 PM | 9 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:45:06 PM | 14 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:45:06 PM | 43 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:45:06 PM | 12 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:45:06 PM | 10 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:49:06 PM | 26 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:49:07 PM | 43 | 1379.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 12 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 33 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 9 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 10 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 9 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 9 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 1 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 6 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 8 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:00 PM | 9 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:02 PM | 49 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:02 PM | 76 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:02 PM | 1 | 1379.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:02 PM | 30 | 1379.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:02 PM | 40 | 1379.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:02 PM | 34 | 1379.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:44 PM | 12 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:44 PM | 19 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:46 PM | 18 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:46 PM | 30 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:46 PM | 15 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:50:46 PM | 23 | 1378.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:50:46 PM | 24 | 1378.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:50:47 PM | 44 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:47 PM | 8 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:49 PM | 28 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:50:49 PM | 44 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:51:01 PM | 78 | 1379.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:51:01 PM | 32 | 1379.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:51:01 PM | 7 | 1379.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:51:01 PM | 15 | 1379.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:51:34 PM | 17 | 1378.50 | XCSE |
97
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 1:51:34 PM | 44 | 1378.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 1:51:34 PM | 12 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:51:34 PM | 69 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:51:34 PM | 8 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:51:34 PM | 22 | 1378.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:52:46 PM | 22 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:52:46 PM | 54 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:53:16 PM | 8 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:53:16 PM | 9 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:53:16 PM | 14 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:53:16 PM | 10 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:53:16 PM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:06 PM | 9 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:06 PM | 32 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:06 PM | 6 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:06 PM | 9 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:06 PM | 8 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:56 PM | 9 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:56 PM | 6 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:56 PM | 10 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:54:56 PM | 10 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:55:59 PM | 78 | 1378.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:55:59 PM | 73 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 1:55:59 PM | 25 | 1378.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 1:55:59 PM | 22 | 1378.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:56:12 PM | 72 | 1377.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:58:48 PM | 43 | 1377.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:58:48 PM | 55 | 1377.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:58:49 PM | 48 | 1377.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:59:14 PM | 28 | 1376.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 1:59:26 PM | 41 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:59:26 PM | 32 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 1:59:43 PM | 72 | 1376.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:00:31 PM | 27 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:00:31 PM | 73 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:00:57 PM | 74 | 1376.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:01:28 PM | 10 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:01:28 PM | 78 | 1376.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:01:28 PM | 9 | 1376.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:01:28 PM | 14 | 1376.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:01:38 PM | 2 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:01:57 PM | 39 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:04:58 PM | 27 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:04:58 PM | 23 | 1376.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:05:19 PM | 39 | 1375.50 | XCSE |
98
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:05:19 PM | 10 | 1375.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:05:19 PM | 73 | 1375.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:05:19 PM | 22 | 1375.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 10 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 9 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 9 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 7 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 8 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 10 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 20 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 9 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 10 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 13 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 11 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 10 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 10 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:06 PM | 8 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:23 PM | 8 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:23 PM | 20 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:06:23 PM | 3 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:25 PM | 44 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:25 PM | 8 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:25 PM | 11 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:25 PM | 9 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:25 PM | 9 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:25 PM | 30 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:25 PM | 17 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:46 PM | 7 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:46 PM | 10 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:46 PM | 10 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:07:46 PM | 3 | 1375.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:08:12 PM | 24 | 1374.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:08:12 PM | 51 | 1374.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:08:12 PM | 15 | 1374.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:09:39 PM | 30 | 1374.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:09:39 PM | 9 | 1374.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:09:39 PM | 17 | 1374.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:09:39 PM | 58 | 1374.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:09:39 PM | 14 | 1374.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:09:39 PM | 8 | 1374.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:09:41 PM | 23 | 1374.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:11:06 PM | 12 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:11:15 PM | 61 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:11:38 PM | 30 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:11:38 PM | 43 | 1374.00 | XCSE |
99
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:11:38 PM | 8 | 1374.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:11:38 PM | 17 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:11:38 PM | 44 | 1374.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:11:38 PM | 34 | 1374.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:11:38 PM | 30 | 1373.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:11:38 PM | 24 | 1373.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:12:16 PM | 9 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:12:16 PM | 12 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:12:16 PM | 9 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:12:16 PM | 10 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:12:16 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:12:16 PM | 10 | 1374.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:12:46 PM | 24 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:13:18 PM | 49 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:25 PM | 41 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:25 PM | 10 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:25 PM | 8 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:25 PM | 10 | 1373.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:25 PM | 49 | 1373.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:14:25 PM | 32 | 1373.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:14:36 PM | 7 | 1372.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:36 PM | 7 | 1372.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:36 PM | 12 | 1372.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:36 PM | 4 | 1372.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:36 PM | 10 | 1372.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:41 PM | 19 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:14:41 PM | 54 | 1375.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 13 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 3 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 43 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 7 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 9 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 15 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 2 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 8 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 12 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 6 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 4 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:10 PM | 9 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:16 PM | 13 | 1376.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:25 PM | 22 | 1377.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:17:30 PM | 12 | 1377.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:31 PM | 73 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:17:31 PM | 5 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:18:09 PM | 73 | 1377.00 | CEUX |
100
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:18:09 PM | 22 | 1377.00 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:21:23 PM | 72 | 1376.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:21:24 PM | 5 | 1376.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:21:24 PM | 36 | 1376.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:31 PM | 5 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:31 PM | 5 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:31 PM | 5 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:31 PM | 30 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:31 PM | 9 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:31 PM | 1 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:31 PM | 5 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:32 PM | 12 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:46 PM | 62 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:22:46 PM | 31 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:49 PM | 62 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:22:49 PM | 31 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:22:51 PM | 15 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:23:12 PM | 5 | 1377.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:23:29 PM | 98 | 1377.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:23:29 PM | 69 | 1377.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:23:29 PM | 42 | 1377.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:23:29 PM | 10 | 1376.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:23:30 PM | 98 | 1377.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:24:48 PM | 4 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:24:49 PM | 73 | 1377.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:24:49 PM | 25 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:24:49 PM | 4 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:24:49 PM | 5 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:24:49 PM | 4 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:25:20 PM | 10 | 1378.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:25:41 PM | 10 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:25:41 PM | 8 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:25:41 PM | 7 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:25:41 PM | 12 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:26:19 PM | 23 | 1380.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:26:19 PM | 62 | 1380.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:26:19 PM | 32 | 1380.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:26:20 PM | 44 | 1380.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:26:41 PM | 12 | 1381.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:26:41 PM | 7 | 1381.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:26:59 PM | 15 | 1381.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:27:14 PM | 10 | 1381.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:27:23 PM | 30 | 1380.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 10 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 17 | 1381.50 | XCSE |
101
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 17 | 1381.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 10 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 1 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 9 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 42 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 7 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 4 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:26 PM | 12 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:36 PM | 17 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:36 PM | 10 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:36 PM | 10 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:36 PM | 10 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:36 PM | 7 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:37 PM | 2 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:37 PM | 12 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:27:42 PM | 4 | 1381.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:27:50 PM | 73 | 1381.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:28:20 PM | 30 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:28:21 PM | 10 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:28:21 PM | 12 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:28:21 PM | 9 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:28:21 PM | 8 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:28:30 PM | 8 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:28:30 PM | 10 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 98 | 1381.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 74 | 1379.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 76 | 1378.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 76 | 1380.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 77 | 1381.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 34 | 1379.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 41 | 1379.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 72 | 1380.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 29 | 1379.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 38 | 1380.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 32 | 1378.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:29:02 PM | 23 | 1378.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:29:03 PM | 22 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:03 PM | 50 | 1377.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:03 PM | 71 | 1377.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:29:36 PM | 10 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:36 PM | 12 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:36 PM | 12 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:46 PM | 8 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:46 PM | 37 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:46 PM | 15 | 1379.00 | XCSE |
102
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:29:46 PM | 11 | 1379.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:29:46 PM | 8 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:46 PM | 8 | 1379.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:29:48 PM | 5 | 1378.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:30:05 PM | 28 | 1379.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:31:09 PM | 1 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:09 PM | 19 | 1382.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:31:09 PM | 57 | 1382.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:31:09 PM | 26 | 1382.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:31:15 PM | 13 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:15 PM | 10 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:15 PM | 22 | 1381.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:31:21 PM | 29 | 1381.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:35 PM | 15 | 1382.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:35 PM | 1 | 1382.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:35 PM | 38 | 1382.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:35 PM | 20 | 1382.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:45 PM | 30 | 1382.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:31:48 PM | 8 | 1383.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:48 PM | 12 | 1383.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:48 PM | 9 | 1383.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:50 PM | 10 | 1383.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:51 PM | 7 | 1383.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:31:54 PM | 13 | 1383.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:32:01 PM | 14 | 1383.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:32:52 PM | 56 | 1384.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:32:52 PM | 29 | 1385.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:32:53 PM | 34 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:33:26 PM | 73 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:33:26 PM | 24 | 1386.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:34:21 PM | 49 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:21 PM | 2 | 1386.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:21 PM | 11 | 1386.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:21 PM | 24 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:21 PM | 4 | 1386.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:21 PM | 10 | 1386.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:21 PM | 74 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:34:21 PM | 23 | 1386.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:34:28 PM | 12 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:28 PM | 33 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:29 PM | 42 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:34:44 PM | 33 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:35:24 PM | 31 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:35:24 PM | 8 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:35:25 PM | 8 | 1386.00 | CEUX |
103
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 10 | 1385.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 5 | 1385.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 67 | 1385.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 14 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 39 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 4 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 31 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 4 | 1385.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 8 | 1385.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 11 | 1385.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 3 | 1385.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 14 | 1385.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:35:27 PM | 26 | 1385.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:35:57 PM | 19 | 1384.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:35:57 PM | 36 | 1384.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:36:05 PM | 42 | 1384.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:05 PM | 56 | 1384.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:07 PM | 21 | 1384.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:38 PM | 19 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:36:39 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:39 PM | 17 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:39 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:39 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:52 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:52 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:52 PM | 11 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:52 PM | 36 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:36:52 PM | 5 | 1387.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:36:52 PM | 5 | 1387.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:36:52 PM | 56 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:36:55 PM | 20 | 1386.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:36:55 PM | 2 | 1386.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 74 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 85 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 24 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 5 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 73 | 1385.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 12 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 9 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 25 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:37:01 PM | 33 | 1385.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:37:30 PM | 8 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:37:33 PM | 28 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:37:33 PM | 25 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:37:33 PM | 40 | 1386.00 | CEUX |
104
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:38:01 PM | 32 | 1385.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:38:12 PM | 14 | 1387.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 14 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 55 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 55 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 36 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 7 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 40 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 55 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 3 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:14 PM | 29 | 1388.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:20 PM | 59 | 1387.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:39:21 PM | 44 | 1387.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:39:49 PM | 23 | 1387.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:39:49 PM | 32 | 1387.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:40:01 PM | 73 | 1386.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:01 PM | 11 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:01 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:01 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:01 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:01 PM | 49 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 30 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 20 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 11 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 26 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:02 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:03 PM | 20 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:03 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:03 PM | 11 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:03 PM | 13 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:03 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:03 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:03 PM | 49 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:03 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:04 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:04 PM | 19 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:04 PM | 49 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:05 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:05 PM | 49 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:05 PM | 10 | 1387.00 | XCSE |
105
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:40:05 PM | 19 | 1387.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:40:05 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:06 PM | 49 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:06 PM | 22 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:06 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:06 PM | 19 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 49 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 19 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 49 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 19 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:07 PM | 19 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:08 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:08 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:08 PM | 49 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:08 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:08 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:08 PM | 17 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:08 PM | 19 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:10 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:10 PM | 7 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:10 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:12 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 6 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 30 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 43 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 1 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 10 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 11 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 16 | 1387.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 74 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 15 | 1387.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:40:13 PM | 31 | 1386.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:40:14 PM | 25 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:40:14 PM | 40 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:41:05 PM | 73 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:41:12 PM | 15 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:41:12 PM | 13 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:41:12 PM | 19 | 1386.00 | XCSE |
106
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:41:12 PM | 24 | 1386.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:41:25 PM | 28 | 1385.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:42:15 PM | 19 | 1385.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:15 PM | 23 | 1386.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:42:15 PM | 13 | 1386.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:42:16 PM | 9 | 1386.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:42:30 PM | 68 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:42:30 PM | 10 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:42:30 PM | 72 | 1385.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:30 PM | 36 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:35 PM | 4 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:35 PM | 11 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:35 PM | 5 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:40 PM | 8 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:43 PM | 4 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:43 PM | 22 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:43 PM | 18 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:43 PM | 5 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:43 PM | 25 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:45 PM | 10 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:52 PM | 19 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:52 PM | 22 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:52 PM | 10 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:52 PM | 11 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:52 PM | 9 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:52 PM | 15 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:42:52 PM | 41 | 1386.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:42:59 PM | 77 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:42:59 PM | 41 | 1386.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:43:00 PM | 13 | 1384.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:43:00 PM | 11 | 1385.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:43:00 PM | 32 | 1385.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:43:00 PM | 24 | 1385.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:43:05 PM | 1 | 1384.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:43:05 PM | 23 | 1384.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:43:05 PM | 42 | 1384.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:43:11 PM | 10 | 1384.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:43:12 PM | 29 | 1384.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:43:12 PM | 30 | 1384.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:43:27 PM | 1 | 1384.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:44:21 PM | 10 | 1384.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:44:21 PM | 30 | 1384.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:44:21 PM | 15 | 1384.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:44:21 PM | 22 | 1384.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:44:22 PM | 20 | 1384.00 | CEUX |
107
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:44:22 PM | 2 | 1384.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:44:26 PM | 9 | 1383.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:44:26 PM | 9 | 1383.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:44:26 PM | 10 | 1383.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:44:26 PM | 10 | 1383.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:11 PM | 74 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:11 PM | 15 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:11 PM | 22 | 1386.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:45:11 PM | 24 | 1386.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:45:20 PM | 10 | 1385.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:21 PM | 3 | 1385.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:23 PM | 4 | 1385.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:33 PM | 78 | 1386.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:43 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:43 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:43 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:43 PM | 13 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:43 PM | 20 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:43 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:43 PM | 19 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:43 PM | 58 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:45 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:45 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:45 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:45 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:45 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:45 PM | 20 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:45 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:45 PM | 20 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:46 PM | 2 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:46 PM | 1 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:47 PM | 11 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:47 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:48 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:48 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:48 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:48 PM | 19 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:48 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:51 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:51 PM | 19 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:51 PM | 1 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:45:52 PM | 14 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:52 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:52 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:52 PM | 10 | 1387.00 | XCSE |
108
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:45:52 PM | 8 | 1387.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:45:52 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:52 PM | 10 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:52 PM | 9 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:53 PM | 8 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:45:56 PM | 7 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:01 PM | 13 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:07 PM | 75 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:07 PM | 22 | 1387.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:46:07 PM | 25 | 1387.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:46:15 PM | 21 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:46:15 PM | 20 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:46:15 PM | 8 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:46:19 PM | 14 | 1387.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:46:20 PM | 74 | 1387.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:26 PM | 20 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:26 PM | 30 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:26 PM | 10 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:46:26 PM | 1 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:46:26 PM | 14 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:46:26 PM | 10 | 1387.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:46:30 PM | 24 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:41 PM | 4 | 1386.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:52 PM | 74 | 1386.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:46:52 PM | 74 | 1386.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:46:52 PM | 28 | 1386.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:47:43 PM | 74 | 1386.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:47:59 PM | 19 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:03 PM | 17 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:06 PM | 12 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:09 PM | 2 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:11 PM | 1 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:11 PM | 1 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:11 PM | 1 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:11 PM | 1 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:15 PM | 22 | 1388.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:48:21 PM | 15 | 1388.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:48:54 PM | 72 | 1389.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:48:54 PM | 9 | 1389.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:48:54 PM | 14 | 1389.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:48:54 PM | 3 | 1389.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:49:24 PM | 9 | 1390.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:49:24 PM | 20 | 1390.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:49:24 PM | 10 | 1390.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:49:24 PM | 8 | 1390.00 | XCSE |
109
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:49:25 PM | 42 | 1390.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:49:41 PM | 20 | 1389.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:49:41 PM | 18 | 1389.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:49:41 PM | 5 | 1389.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:49:41 PM | 45 | 1389.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:49:41 PM | 5 | 1389.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:49:41 PM | 22 | 1389.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:49:41 PM | 22 | 1389.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:50:27 PM | 56 | 1390.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:50:27 PM | 3 | 1390.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:50:30 PM | 68 | 1391.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:50:32 PM | 7 | 1391.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:50:32 PM | 4 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:50:32 PM | 1 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:50:32 PM | 1 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:50:32 PM | 12 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:50:32 PM | 25 | 1391.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:50:46 PM | 56 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:50:46 PM | 19 | 1390.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:50:48 PM | 60 | 1390.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:50:48 PM | 3 | 1390.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:51:23 PM | 31 | 1392.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:23 PM | 46 | 1392.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:23 PM | 10 | 1391.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:23 PM | 10 | 1391.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:23 PM | 2 | 1391.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:23 PM | 8 | 1391.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:24 PM | 53 | 1392.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:24 PM | 27 | 1392.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:31 PM | 6 | 1391.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:31 PM | 44 | 1391.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:31 PM | 26 | 1391.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:51:34 PM | 2 | 1391.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:51:35 PM | 52 | 1390.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:35 PM | 21 | 1390.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:35 PM | 71 | 1391.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:35 PM | 41 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:35 PM | 31 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:35 PM | 4 | 1390.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:51:35 PM | 18 | 1390.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:51:46 PM | 10 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:59 PM | 77 | 1390.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:51:59 PM | 59 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:59 PM | 6 | 1390.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:51:59 PM | 6 | 1390.50 | TQEX |
110
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:51:59 PM | 17 | 1390.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:51:59 PM | 2 | 1390.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:51:59 PM | 2 | 1390.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:52:29 PM | 24 | 1390.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:52:54 PM | 2 | 1392.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:52:54 PM | 8 | 1392.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:53:26 PM | 8 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:53:31 PM | 74 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:53:50 PM | 73 | 1392.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:53:50 PM | 73 | 1393.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:53:50 PM | 10 | 1392.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:53:50 PM | 41 | 1393.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:54:16 PM | 69 | 1393.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:54:16 PM | 9 | 1393.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:54:16 PM | 4 | 1393.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:54:16 PM | 72 | 1393.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:54:16 PM | 28 | 1393.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 2:54:20 PM | 76 | 1393.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:54:27 PM | 5 | 1392.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:54:31 PM | 5 | 1392.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:54:31 PM | 15 | 1392.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:55:28 PM | 2 | 1392.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:55:28 PM | 28 | 1392.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:55:30 PM | 48 | 1392.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:56:07 PM | 72 | 1392.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:56:38 PM | 10 | 1394.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:56:38 PM | 21 | 1394.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:56:51 PM | 30 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:56:51 PM | 47 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:56:51 PM | 46 | 1394.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:57:09 PM | 15 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:57:09 PM | 9 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:57:24 PM | 22 | 1393.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 2:57:29 PM | 8 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:57:29 PM | 32 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:57:29 PM | 31 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:57:29 PM | 1 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:57:29 PM | 16 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:57:29 PM | 10 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:58:45 PM | 3 | 1396.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 2:58:55 PM | 29 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:58:55 PM | 4 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:58:55 PM | 65 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:58:55 PM | 95 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:59:28 PM | 1 | 1396.00 | CEUX |
111
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 2:59:54 PM | 12 | 1398.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 2:59:54 PM | 49 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:59:54 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:59:54 PM | 27 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:59:56 PM | 52 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 2:59:56 PM | 8 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:00:01 PM | 9 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:00:09 PM | 13 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:00:10 PM | 78 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:00:10 PM | 45 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:00:10 PM | 29 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:00:10 PM | 1 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:00:10 PM | 22 | 1398.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 2 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 21 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 9 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 10 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 10 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 5 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 4 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 2 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 5 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:01:01 PM | 23 | 1401.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:01:22 PM | 76 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:22 PM | 76 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:01:22 PM | 19 | 1402.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:01:22 PM | 3 | 1402.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:01:23 PM | 28 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:23 PM | 77 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:23 PM | 48 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:01:23 PM | 47 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:01:23 PM | 28 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:01:23 PM | 76 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:01:23 PM | 31 | 1401.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:01:23 PM | 22 | 1400.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:02:03 PM | 72 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:02:03 PM | 22 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:02:03 PM | 26 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:02:13 PM | 75 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:02:13 PM | 42 | 1402.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:02:35 PM | 30 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:02:35 PM | 22 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:03:07 PM | 4 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:03:07 PM | 9 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:03:15 PM | 25 | 1402.50 | XCSE |
112
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:03:34 PM | 34 | 1402.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:03:34 PM | 77 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:03:34 PM | 23 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:03:43 PM | 17 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:03:43 PM | 40 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:04:28 PM | 29 | 1403.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:04:51 PM | 45 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:04:51 PM | 9 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:04:51 PM | 10 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:04:52 PM | 12 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:05:27 PM | 54 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:05:27 PM | 3 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:05:31 PM | 63 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:06:45 PM | 32 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:07 PM | 19 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:07 PM | 17 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:07:13 PM | 50 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 30 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 25 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 13 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 26 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 43 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 16 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 73 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 76 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 73 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 9 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 22 | 1403.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 22 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 22 | 1403.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:07:15 PM | 29 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:07:17 PM | 40 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:18 PM | 10 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:18 PM | 14 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:21 PM | 33 | 1401.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:07:27 PM | 78 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:07:27 PM | 34 | 1400.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:09:00 PM | 40 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:09:35 PM | 4 | 1406.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:09:41 PM | 55 | 1406.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:09:41 PM | 17 | 1406.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:09:42 PM | 9 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:09:49 PM | 73 | 1406.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:03 PM | 11 | 1409.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:04 PM | 73 | 1408.50 | XCSE |
113
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:10:04 PM | 30 | 1409.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:10:04 PM | 9 | 1409.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:04 PM | 12 | 1409.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:04 PM | 43 | 1409.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:04 PM | 4 | 1409.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:04 PM | 72 | 1408.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:10:04 PM | 33 | 1409.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:10:06 PM | 72 | 1408.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:06 PM | 52 | 1408.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:10:06 PM | 22 | 1408.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 9 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 73 | 1408.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 15 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 15 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 10 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 5 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 15 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 5 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 48 | 1407.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 14 | 1408.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 42 | 1409.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 13 | 1408.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 24 | 1407.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:10:35 PM | 30 | 1408.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:11:10 PM | 22 | 1408.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:11:22 PM | 35 | 1407.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:11:22 PM | 41 | 1407.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:11:22 PM | 27 | 1407.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:11:22 PM | 23 | 1407.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:12:00 PM | 72 | 1407.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:12:00 PM | 22 | 1407.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:12:00 PM | 22 | 1407.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:12:00 PM | 19 | 1407.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:12:03 PM | 5 | 1407.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:12:06 PM | 26 | 1406.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:12:06 PM | 10 | 1406.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:12:06 PM | 40 | 1406.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:12:11 PM | 8 | 1406.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:12:13 PM | 41 | 1405.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:12:13 PM | 24 | 1406.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:12:43 PM | 78 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:12:43 PM | 22 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:12:43 PM | 24 | 1405.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:12:43 PM | 24 | 1403.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:12:44 PM | 24 | 1403.00 | XCSE |
114
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:12:44 PM | 50 | 1403.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:12:59 PM | 53 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:12:59 PM | 35 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:12:59 PM | 17 | 1402.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:13:19 PM | 43 | 1404.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:13:19 PM | 22 | 1403.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:14:07 PM | 18 | 1404.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:14:10 PM | 62 | 1404.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:14:10 PM | 24 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:14:10 PM | 16 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:14:10 PM | 3 | 1404.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:14:36 PM | 10 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:14:36 PM | 4 | 1404.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:14:36 PM | 16 | 1404.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:14:40 PM | 22 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:14:40 PM | 30 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:14:48 PM | 7 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:14:48 PM | 24 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:15:03 PM | 43 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:03 PM | 22 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 47 | 1400.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 21 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 36 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 5 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 20 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 26 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 6 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 2 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:15:32 PM | 23 | 1401.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:15:33 PM | 36 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:33 PM | 7 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:33 PM | 19 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:15:48 PM | 60 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:51 PM | 16 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:15:51 PM | 7 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:15:55 PM | 3 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:55 PM | 21 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:15:55 PM | 9 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:16:14 PM | 29 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:16:14 PM | 29 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:17:09 PM | 19 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:17:13 PM | 25 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:17:13 PM | 7 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:17:13 PM | 29 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:17:13 PM | 3 | 1398.00 | CEUX |
115
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:17:13 PM | 25 | 1396.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:17:13 PM | 23 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:17:13 PM | 22 | 1397.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:17:16 PM | 60 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:18:13 PM | 15 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:18:34 PM | 17 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:19:56 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:19:56 PM | 13 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:19:56 PM | 41 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:20:34 PM | 17 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:20:34 PM | 30 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:20:34 PM | 22 | 1396.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:21:09 PM | 76 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:21:09 PM | 39 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:21:09 PM | 22 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:21:17 PM | 16 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:21:17 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:21:17 PM | 42 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:21:17 PM | 42 | 1397.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:21:17 PM | 22 | 1397.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:21:24 PM | 10 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:21:32 PM | 10 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:21:32 PM | 10 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:21:38 PM | 4 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:21:50 PM | 39 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:05 PM | 55 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:22:08 PM | 29 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:19 PM | 11 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:19 PM | 11 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:20 PM | 47 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:22:28 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:36 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:37 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:37 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:46 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:52 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:22:58 PM | 12 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:23:09 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:24:34 PM | 41 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:24:34 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:24:34 PM | 24 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:24:34 PM | 73 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:25:24 PM | 1 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:25:24 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:25:24 PM | 2 | 1399.00 | XCSE |
116
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:25:24 PM | 7 | 1399.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:25:24 PM | 14 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:25:58 PM | 7 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:25:58 PM | 31 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:25:58 PM | 42 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:25:58 PM | 18 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:01 PM | 42 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:01 PM | 12 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:01 PM | 10 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:01 PM | 8 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:01 PM | 10 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 11 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 31 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 18 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 42 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 76 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 22 | 1403.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 11 | 1403.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 4 | 1403.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:26:07 PM | 11 | 1403.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:26:20 PM | 10 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:20 PM | 30 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:20 PM | 10 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:20 PM | 1 | 1403.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:26:20 PM | 44 | 1403.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:26:20 PM | 4 | 1403.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:26:20 PM | 2 | 1403.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:26:20 PM | 22 | 1403.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:26:32 PM | 76 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:32 PM | 67 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:26:32 PM | 78 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:26:32 PM | 32 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:26:32 PM | 28 | 1403.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:27:09 PM | 74 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:27:09 PM | 23 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:27:09 PM | 3 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:27:09 PM | 21 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:27:55 PM | 77 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:27:55 PM | 28 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:27:55 PM | 23 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:27:55 PM | 2 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:27:58 PM | 77 | 1400.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:28:19 PM | 7 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:28:19 PM | 69 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:28:56 PM | 5 | 1402.00 | CEUX |
117
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:29:11 PM | 9 | 1401.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:29:11 PM | 18 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:29:11 PM | 5 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:29:11 PM | 22 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:29:11 PM | 42 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:29:15 PM | 12 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:29:16 PM | 20 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:29:16 PM | 34 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:30:15 PM | 73 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:30:15 PM | 41 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:31:07 PM | 72 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:31:07 PM | 60 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:31:10 PM | 77 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:31:10 PM | 5 | 1401.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:31:10 PM | 18 | 1401.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:31:50 PM | 16 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:32:46 PM | 4 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:01 PM | 10 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:01 PM | 4 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:01 PM | 9 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 8 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 24 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 30 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 77 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 26 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 74 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 10 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 48 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 22 | 1401.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:33:07 PM | 22 | 1402.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:33:30 PM | 73 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:30 PM | 10 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:30 PM | 64 | 1402.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:33:30 PM | 40 | 1402.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:34:17 PM | 72 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:34:17 PM | 48 | 1405.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:34:17 PM | 22 | 1405.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:34:17 PM | 22 | 1405.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:34:28 PM | 45 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:35:06 PM | 17 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:35:06 PM | 13 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:35:06 PM | 5 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:35:06 PM | 14 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:35:17 PM | 77 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:35:38 PM | 19 | 1404.50 | CEUX |
118
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:35:38 PM | 34 | 1404.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:36:01 PM | 10 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:36:01 PM | 10 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:36:01 PM | 9 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:36:01 PM | 8 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:36:40 PM | 38 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:36:40 PM | 60 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:36:45 PM | 5 | 1404.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:36:56 PM | 6 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:36:56 PM | 32 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:37:16 PM | 47 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:37:36 PM | 41 | 1404.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:37:36 PM | 11 | 1404.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:37:36 PM | 43 | 1404.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:37:42 PM | 50 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:37:42 PM | 74 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:37:42 PM | 30 | 1404.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:39:58 PM | 42 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:39:58 PM | 23 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:39:58 PM | 22 | 1403.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:40:04 PM | 46 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:40:07 PM | 33 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:40:08 PM | 42 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:40:08 PM | 44 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:40:08 PM | 12 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:40:12 PM | 13 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:40:12 PM | 11 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:40:13 PM | 30 | 1402.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:40:19 PM | 53 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:41:10 PM | 38 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:41:10 PM | 60 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:41:10 PM | 29 | 1404.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:41:10 PM | 8 | 1404.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:41:24 PM | 73 | 1405.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:41:24 PM | 24 | 1405.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:41:44 PM | 30 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:41:44 PM | 9 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:41:44 PM | 22 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:41:44 PM | 37 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:41:53 PM | 14 | 1406.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 40 | 1406.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 4 | 1406.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 40 | 1406.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 19 | 1406.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 33 | 1406.50 | XCSE |
119
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 10 | 1406.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 30 | 1406.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 47 | 1406.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 12 | 1406.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:42:12 PM | 22 | 1406.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:42:28 PM | 77 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:28 PM | 73 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:28 PM | 77 | 1405.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:42:28 PM | 37 | 1405.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:42:40 PM | 72 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:42:41 PM | 78 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:41 PM | 73 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:42:42 PM | 11 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:42 PM | 12 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:42:46 PM | 49 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:42:56 PM | 72 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:43:26 PM | 62 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:43:26 PM | 22 | 1400.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:44:03 PM | 22 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:44:53 PM | 4 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:46:20 PM | 13 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:46:20 PM | 25 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:46:20 PM | 1 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:46:20 PM | 10 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:46:20 PM | 9 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:46:46 PM | 72 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:02 PM | 11 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:02 PM | 1 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:02 PM | 7 | 1400.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:02 PM | 30 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:02 PM | 27 | 1400.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:48:02 PM | 3 | 1400.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:48:02 PM | 21 | 1400.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:48:03 PM | 13 | 1400.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:21 PM | 2 | 1400.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:48:21 PM | 2 | 1400.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:48:21 PM | 20 | 1400.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:48:21 PM | 3 | 1400.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:48:48 PM | 42 | 1400.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:48 PM | 77 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:48 PM | 9 | 1400.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:48 PM | 20 | 1400.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:50 PM | 1 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:50 PM | 12 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:48:50 PM | 9 | 1400.00 | XCSE |
120
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:48:50 PM | 14 | 1400.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:48:57 PM | 9 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:06 PM | 14 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:49:06 PM | 61 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:49:06 PM | 1 | 1401.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:49:07 PM | 9 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:07 PM | 21 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:09 PM | 20 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:09 PM | 26 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:09 PM | 42 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:09 PM | 10 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:10 PM | 37 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:10 PM | 10 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:10 PM | 8 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:10 PM | 42 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:10 PM | 8 | 1401.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:17 PM | 76 | 1400.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:49:21 PM | 27 | 1400.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:49:22 PM | 14 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:49:22 PM | 4 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:49:44 PM | 22 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:44 PM | 22 | 1399.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:49:45 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:45 PM | 6 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:45 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:45 PM | 30 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:45 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:49:45 PM | 18 | 1399.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:49:46 PM | 22 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 42 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 37 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 42 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 37 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 14 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 36 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 2 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 15 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 71 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 7 | 1399.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:51:53 PM | 15 | 1399.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:51:56 PM | 17 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:51:56 PM | 11 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:52:46 PM | 9 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:52:46 PM | 9 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:52:46 PM | 42 | 1398.50 | XCSE |
121
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:52:46 PM | 25 | 1399.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:52:46 PM | 10 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:52:46 PM | 25 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:52:46 PM | 75 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:52:46 PM | 22 | 1398.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:53:35 PM | 9 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:53:35 PM | 25 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:58 PM | 2 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:58 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:58 PM | 14 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:58 PM | 42 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:58 PM | 30 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:58 PM | 25 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:58 PM | 36 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:54:58 PM | 24 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:54:59 PM | 18 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:59 PM | 39 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:59 PM | 29 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:59 PM | 30 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:59 PM | 42 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:54:59 PM | 30 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:56:09 PM | 74 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:56:09 PM | 37 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:56:09 PM | 77 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:56:09 PM | 40 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:56:09 PM | 27 | 1397.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:56:09 PM | 23 | 1398.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 3:56:09 PM | 22 | 1397.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:56:09 PM | 33 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:56:10 PM | 32 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:56:16 PM | 1 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:56:16 PM | 44 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:56:16 PM | 12 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:56:17 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:56:17 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:56:56 PM | 34 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:56:56 PM | 41 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:57:07 PM | 29 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:57:07 PM | 18 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:57:07 PM | 30 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:57:07 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:57:07 PM | 2 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:57:07 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:57:08 PM | 98 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:57:08 PM | 98 | 1399.00 | XCSE |
122
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 3:57:21 PM | 29 | 1397.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 3:57:21 PM | 46 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:57:21 PM | 32 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:57:21 PM | 40 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 3:57:39 PM | 9 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:59:49 PM | 76 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 3:59:49 PM | 32 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:59:49 PM | 24 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:59:49 PM | 25 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:59:52 PM | 28 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 3:59:52 PM | 25 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:00:03 PM | 26 | 1398.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 26 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 8 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 1 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 10 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 8 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 36 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 4 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 5 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:05 PM | 5 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:11 PM | 15 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:00:11 PM | 1 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:00:11 PM | 4 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:11 PM | 5 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:11 PM | 5 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:11 PM | 5 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:12 PM | 15 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:00:45 PM | 74 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:01:06 PM | 41 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:06 PM | 12 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:06 PM | 45 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:06 PM | 77 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:06 PM | 36 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:01:06 PM | 22 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:01:07 PM | 12 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:07 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:07 PM | 8 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:07 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:07 PM | 78 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:07 PM | 45 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:07 PM | 32 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 32 | 1398.00 | XCSE |
123
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 78 | 1397.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 45 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 77 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 2 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 72 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 5 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:01:21 PM | 33 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:01:22 PM | 11 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:22 PM | 9 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:22 PM | 16 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:34 PM | 20 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:34 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:34 PM | 7 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:34 PM | 45 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:34 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:01:34 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 73 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 45 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 2 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 14 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 10 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 41 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 75 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 75 | 1396.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 25 | 1396.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 11 | 1396.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 11 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 19 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:05:02 PM | 15 | 1396.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 24 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 8 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 45 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:12 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:17 PM | 10 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:17 PM | 6 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:17 PM | 5 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:17 PM | 5 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:05:47 PM | 73 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:05:47 PM | 36 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:05:47 PM | 4 | 1398.50 | CEUX |
124
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:05:47 PM | 3 | 1398.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:05:47 PM | 34 | 1398.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:06:21 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:06:21 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:06:21 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:06:21 PM | 6 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:06:21 PM | 24 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:07:20 PM | 36 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:07:20 PM | 33 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:07:48 PM | 8 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:07:48 PM | 36 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:07:48 PM | 21 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:07:48 PM | 14 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:07:48 PM | 29 | 1400.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:07:55 PM | 1 | 1400.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:08:07 PM | 44 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:07 PM | 75 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:07 PM | 15 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:08:07 PM | 24 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:08:07 PM | 34 | 1400.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:08:11 PM | 30 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:11 PM | 36 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:08:11 PM | 72 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:08:21 PM | 19 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:21 PM | 41 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:21 PM | 3 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:22 PM | 10 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:40 PM | 26 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:40 PM | 30 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:08:40 PM | 36 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:08:59 PM | 74 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:09:02 PM | 12 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:09:36 PM | 19 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:36 PM | 30 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:40 PM | 10 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 28 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 48 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 45 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 11 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 30 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 25 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 1 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 9 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 10 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 6 | 1399.50 | XCSE |
125
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 30 | 1399.00 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:10:42 PM | 29 | 1399.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:10:43 PM | 9 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:43 PM | 30 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:43 PM | 10 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:43 PM | 9 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 77 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 12 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 4 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 5 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 4 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:10:48 PM | 25 | 1399.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:11:09 PM | 73 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:11:10 PM | 3 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 15 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 38 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 44 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 37 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 6 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 11 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:12 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 16 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 45 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 39 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 3 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:13 PM | 38 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 14 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 25 | 1399.00 | XCSE |
126
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 9 | 1399.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 14 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 45 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 38 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:14 PM | 13 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:15 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:15 PM | 9 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:15 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:16 PM | 8 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:23 PM | 13 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:41 PM | 9 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:41 PM | 38 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:41 PM | 9 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:41 PM | 8 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:41 PM | 17 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:41 PM | 9 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:41 PM | 8 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:48 PM | 36 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:48 PM | 10 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:11:55 PM | 13 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 10 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 8 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 17 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 45 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 3 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 8 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 32 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 10 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 10 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:37 PM | 8 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:46 PM | 9 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:50 PM | 14 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:12:53 PM | 36 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:12:56 PM | 7 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:12:57 PM | 8 | 1400.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:05 PM | 36 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:06 PM | 41 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:06 PM | 20 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:28 PM | 47 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:29 PM | 5 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:29 PM | 4 | 1400.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:29 PM | 36 | 1400.00 | CEUX |
127
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:13:29 PM | 5 | 1400.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:13:44 PM | 12 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:44 PM | 39 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:44 PM | 10 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:44 PM | 4 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:44 PM | 36 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:44 PM | 4 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:44 PM | 5 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:45 PM | 44 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:54 PM | 17 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:54 PM | 10 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:54 PM | 7 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:54 PM | 18 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:54 PM | 10 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:54 PM | 9 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:54 PM | 7 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:54 PM | 22 | 1399.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:55 PM | 2 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:55 PM | 10 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:55 PM | 10 | 1399.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:58 PM | 74 | 1399.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:13:58 PM | 75 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:13:58 PM | 22 | 1399.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:13:58 PM | 23 | 1399.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:14:18 PM | 78 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:14:18 PM | 23 | 1398.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:14:18 PM | 10 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:14:26 PM | 72 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:14:26 PM | 16 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:14:27 PM | 25 | 1397.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:15:02 PM | 27 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:15:02 PM | 19 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:15:02 PM | 16 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:15:04 PM | 5 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:15:18 PM | 53 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:15:59 PM | 10 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:16:08 PM | 5 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:16:29 PM | 10 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:16:29 PM | 12 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:16:29 PM | 11 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:16:59 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:16:59 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:16:59 PM | 1 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:16:59 PM | 45 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:16:59 PM | 9 | 1397.00 | XCSE |
128
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:16:59 PM | 8 | 1397.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:16:59 PM | 32 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:17:14 PM | 30 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:17:14 PM | 20 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:17:14 PM | 15 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:17:23 PM | 45 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:23 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:23 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:23 PM | 26 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:23 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 8 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 9 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 1 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 10 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 11 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 44 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 29 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 12 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 45 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 11 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:53 PM | 22 | 1396.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:17:54 PM | 17 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:54 PM | 2 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:55 PM | 13 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:55 PM | 3 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:55 PM | 25 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:55 PM | 13 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:56 PM | 18 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:56 PM | 8 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:56 PM | 9 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:56 PM | 1 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:58 PM | 9 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:17:58 PM | 10 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:18:09 PM | 28 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:18:09 PM | 17 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 26 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 7 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 8 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 17 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 8 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 8 | 1396.50 | XCSE |
129
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 78 | 1396.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 10 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 28 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:18:39 PM | 21 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:18:40 PM | 11 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:19:08 PM | 72 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:20:49 PM | 76 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:20:50 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:20:51 PM | 2 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:20:51 PM | 6 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:21:11 PM | 75 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:21:11 PM | 32 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:21:29 PM | 19 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:21:31 PM | 7 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 15 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 45 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 12 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 1 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 1 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 69 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 31 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:22:08 PM | 37 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:22:28 PM | 65 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:22:34 PM | 19 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:22:45 PM | 32 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:22:52 PM | 21 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:22:55 PM | 49 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:23:03 PM | 12 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:23:03 PM | 30 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:23:03 PM | 34 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:23:08 PM | 44 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:23:08 PM | 4 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:23:59 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:23:59 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:23:59 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:01 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:13 PM | 12 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:13 PM | 19 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:24:13 PM | 36 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:24:17 PM | 45 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:17 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:17 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:17 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:17 PM | 8 | 1397.00 | XCSE |
130
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:24:17 PM | 16 | 1397.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 43 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 41 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 11 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 18 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:18 PM | 28 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:19 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:24:44 PM | 1 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:24:44 PM | 30 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:24:44 PM | 1 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:24:44 PM | 16 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:24:44 PM | 7 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:25:29 PM | 17 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:25:29 PM | 9 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:25:29 PM | 21 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:25:29 PM | 12 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 3 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 46 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 42 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 30 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 14 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 11 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 12 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 13 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 45 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 28 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 26 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 24 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 29 | 1396.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:26:08 PM | 25 | 1396.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 45 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 28 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 9 | 1397.00 | XCSE |
131
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 8 | 1397.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 25 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 1 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 45 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:09 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:10 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:10 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:10 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:10 PM | 2 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:10 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:10 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:10 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:11 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:11 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:11 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:11 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:11 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:11 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:11 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:13 PM | 14 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:15 PM | 29 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:15 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:16 PM | 29 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:16 PM | 36 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:21 PM | 78 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:26:56 PM | 12 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:26:56 PM | 16 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:27:04 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:08 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:08 PM | 42 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:08 PM | 28 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:08 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:08 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:27 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:27 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:27 PM | 23 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:27 PM | 5 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:27 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:54 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:54 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:27:54 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:28:11 PM | 10 | 1397.50 | XCSE |
132
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:28:14 PM | 7 | 1397.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:28:32 PM | 12 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:28:37 PM | 10 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:28:37 PM | 11 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:29:06 PM | 9 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:29:50 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:29:50 PM | 5 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:29:54 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:29:54 PM | 25 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:29:54 PM | 1 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 75 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 42 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 36 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 30 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 30 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 37 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 20 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:30:03 PM | 27 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:30:05 PM | 19 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:05 PM | 30 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:05 PM | 2 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:05 PM | 12 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:05 PM | 35 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:05 PM | 36 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:05 PM | 5 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:25 PM | 1 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:34 PM | 29 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:34 PM | 30 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:34 PM | 24 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:34 PM | 1 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:34 PM | 13 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:34 PM | 2 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:34 PM | 12 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:34 PM | 2 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:40 PM | 45 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:40 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:40 PM | 8 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:41 PM | 7 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:46 PM | 11 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 45 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 75 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 9 | 1398.00 | XCSE |
133
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 10 | 1398.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 36 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 28 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 19 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:30:50 PM | 4 | 1397.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:30:51 PM | 5 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:51 PM | 5 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:51 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:52 PM | 12 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:52 PM | 4 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:52 PM | 15 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:30:52 PM | 19 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:31:05 PM | 13 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:31:33 PM | 19 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:31:33 PM | 24 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:31:35 PM | 22 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:31:41 PM | 10 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:31:52 PM | 78 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:31:52 PM | 48 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:31:52 PM | 75 | 1396.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:31:52 PM | 39 | 1395.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:31:52 PM | 23 | 1395.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:31:52 PM | 28 | 1396.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:31:52 PM | 38 | 1395.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:31:52 PM | 25 | 1396.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:31:56 PM | 14 | 1395.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:31:56 PM | 10 | 1395.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:31:56 PM | 11 | 1395.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:31:56 PM | 13 | 1395.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:31:56 PM | 1 | 1395.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:31:56 PM | 41 | 1395.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:32:15 PM | 24 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:32:15 PM | 31 | 1394.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:32:15 PM | 24 | 1394.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:32:19 PM | 54 | 1394.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:32:26 PM | 43 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:32:26 PM | 8 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:32:58 PM | 2 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:32:58 PM | 43 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:00 PM | 32 | 1394.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:33:14 PM | 45 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:14 PM | 10 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:14 PM | 8 | 1393.50 | XCSE |
134
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:33:14 PM | 22 | 1393.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:33:14 PM | 10 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:14 PM | 76 | 1393.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:33:26 PM | 7 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:26 PM | 16 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:26 PM | 17 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:38 PM | 38 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:39 PM | 31 | 1393.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:49 PM | 34 | 1393.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:33:49 PM | 17 | 1393.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:33:57 PM | 9 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:57 PM | 5 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:33:57 PM | 27 | 1394.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:06 PM | 16 | 1394.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:34:16 PM | 19 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:16 PM | 9 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:17 PM | 10 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:17 PM | 12 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:26 PM | 8 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:26 PM | 9 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:26 PM | 19 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:36 PM | 14 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:36 PM | 5 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:38 PM | 19 | 1394.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:34:46 PM | 8 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:46 PM | 8 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:47 PM | 15 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:56 PM | 7 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:34:56 PM | 17 | 1394.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:35:22 PM | 40 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:35:22 PM | 34 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:35:22 PM | 39 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:35:22 PM | 10 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:35:22 PM | 23 | 1394.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:35:30 PM | 33 | 1394.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:36:02 PM | 36 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:36:03 PM | 10 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:03 PM | 9 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:11 PM | 9 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:11 PM | 10 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:11 PM | 45 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:11 PM | 11 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:11 PM | 24 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:11 PM | 10 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:11 PM | 9 | 1394.00 | CEUX |
135
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:36:11 PM | 3 | 1394.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:36:13 PM | 3 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:20 PM | 6 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:36:20 PM | 30 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:36:21 PM | 41 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:36:44 PM | 9 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:44 PM | 10 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:36:44 PM | 36 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:36:45 PM | 28 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:36:59 PM | 53 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:37:00 PM | 45 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:37:00 PM | 18 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:37:00 PM | 19 | 1394.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:37:00 PM | 55 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:37:27 PM | 77 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:37:27 PM | 11 | 1395.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:37:27 PM | 9 | 1395.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:37:31 PM | 65 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:37:31 PM | 13 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:37:31 PM | 43 | 1396.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:37:31 PM | 16 | 1395.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:37:31 PM | 19 | 1396.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:37:31 PM | 3 | 1396.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:37:31 PM | 35 | 1396.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:38:04 PM | 25 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:11 PM | 61 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:11 PM | 48 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:11 PM | 17 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:11 PM | 72 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:11 PM | 36 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:38:11 PM | 27 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:38:11 PM | 29 | 1397.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:38:11 PM | 23 | 1398.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:38:26 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:26 PM | 22 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:26 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:26 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:26 PM | 13 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:26 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:46 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:46 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:46 PM | 22 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:46 PM | 12 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:46 PM | 8 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:38:46 PM | 13 | 1397.00 | XCSE |
136
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:38:49 PM | 76 | 1395.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:38:49 PM | 4 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:38:49 PM | 7 | 1395.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:38:49 PM | 3 | 1395.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:38:49 PM | 3 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:38:50 PM | 4 | 1394.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:39:26 PM | 11 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:26 PM | 9 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:26 PM | 7 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:26 PM | 13 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:26 PM | 10 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:45 PM | 2 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:45 PM | 10 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:45 PM | 9 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:45 PM | 17 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:49 PM | 10 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:49 PM | 9 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:49 PM | 10 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:39:49 PM | 22 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:40:18 PM | 42 | 1395.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:40:26 PM | 3 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:40:27 PM | 1 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:40:27 PM | 6 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:16 PM | 4 | 1396.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:41:16 PM | 4 | 1396.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:41:16 PM | 36 | 1396.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:41:22 PM | 32 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:22 PM | 19 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:22 PM | 2 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:22 PM | 45 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:26 PM | 9 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:26 PM | 8 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:38 PM | 63 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:55 PM | 4 | 1396.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:41:56 PM | 27 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:42:24 PM | 44 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:24 PM | 54 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:25 PM | 12 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:42:27 PM | 20 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:42:28 PM | 66 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:42:29 PM | 78 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:29 PM | 19 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:42:29 PM | 27 | 1398.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:42:29 PM | 23 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:42:50 PM | 36 | 1397.50 | CEUX |
137
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:42:50 PM | 34 | 1397.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:42:50 PM | 21 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:42:50 PM | 23 | 1397.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:42:50 PM | 23 | 1397.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:42:51 PM | 50 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:51 PM | 45 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:51 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:51 PM | 29 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:51 PM | 10 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:51 PM | 38 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:51 PM | 5 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:51 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 8 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 30 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 8 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 30 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 8 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:42:52 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:06 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:08 PM | 53 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:08 PM | 9 | 1398.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:24 PM | 19 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:43:36 PM | 13 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:36 PM | 27 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:36 PM | 4 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:36 PM | 45 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:36 PM | 9 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:40 PM | 7 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:43:40 PM | 63 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:43:52 PM | 25 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:43:52 PM | 56 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:43:52 PM | 22 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:44:24 PM | 8 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:44:24 PM | 9 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:44:24 PM | 14 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:44:24 PM | 41 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:44:31 PM | 78 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:44:31 PM | 36 | 1398.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:44:54 PM | 22 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:45:12 PM | 73 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:45:12 PM | 24 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:45:28 PM | 42 | 1397.50 | XCSE |
138
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:45:40 PM | 35 | 1397.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:45:44 PM | 36 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:45:44 PM | 21 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:45:44 PM | 9 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:46:02 PM | 5 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:02 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:02 PM | 36 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:02 PM | 5 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:03 PM | 11 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:03 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:07 PM | 7 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:07 PM | 14 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:08 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:09 PM | 12 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:13 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:14 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:18 PM | 11 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:18 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:19 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:23 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:23 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:24 PM | 13 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 78 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 10 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 5 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 45 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 4 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 65 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 4 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:29 PM | 27 | 1397.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:46:30 PM | 16 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:30 PM | 12 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:46:30 PM | 15 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:30 PM | 37 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:46:41 PM | 9 | 1397.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:47:01 PM | 20 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:47:01 PM | 36 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:47:01 PM | 8 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:47:01 PM | 34 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:47:01 PM | 24 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:47:02 PM | 7 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:47:09 PM | 15 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:47:19 PM | 11 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:47:19 PM | 15 | 1397.50 | CEUX |
139
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:47:19 PM | 17 | 1397.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:48:21 PM | 35 | 1396.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:48:22 PM | 9 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:48:22 PM | 63 | 1397.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:47 PM | 9 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:47 PM | 36 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:54 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:49:54 PM | 8 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:49:54 PM | 9 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:49:54 PM | 10 | 1397.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:49:54 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:54 PM | 5 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:54 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:55 PM | 9 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:55 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:55 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:55 PM | 23 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:55 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:49:55 PM | 2 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:49:55 PM | 2 | 1397.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:49:58 PM | 8 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:50:16 PM | 4 | 1397.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:50:16 PM | 39 | 1398.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:50:19 PM | 98 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:50:19 PM | 78 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:50:19 PM | 74 | 1398.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:50:20 PM | 13 | 1398.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:50:31 PM | 36 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:50:31 PM | 78 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:50:31 PM | 24 | 1399.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:50:31 PM | 2 | 1399.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:50:31 PM | 2 | 1399.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:50:37 PM | 32 | 1398.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:00 PM | 71 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:00 PM | 27 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:00 PM | 24 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:00 PM | 11 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:51:00 PM | 11 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:51:09 PM | 74 | 1401.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:09 PM | 32 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:09 PM | 2 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:51:09 PM | 11 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:51:09 PM | 2 | 1402.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:51:09 PM | 23 | 1401.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:51:09 PM | 29 | 1401.50 | AQEU |
140
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:51:16 PM | 77 | 1401.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:51:23 PM | 25 | 1402.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:46 PM | 3 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:46 PM | 11 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:46 PM | 22 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:47 PM | 36 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:47 PM | 25 | 1403.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 8 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 73 | 1402.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 10 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 17 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 45 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 24 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 9 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 45 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 28 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 10 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 25 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 4 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 5 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 36 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 2 | 1403.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 44 | 1402.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 31 | 1402.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:51:51 PM | 10 | 1402.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 8 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 13 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 9 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 45 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 8 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 9 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 45 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 8 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 9 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 30 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 2 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 6 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 1 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 8 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 45 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:51:52 PM | 14 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:03 PM | 10 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:03 PM | 45 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:03 PM | 31 | 1403.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:03 PM | 9 | 1403.00 | XCSE |
141
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:52:03 PM | 3 | 1403.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:52:19 PM | 30 | 1403.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:52:19 PM | 3 | 1403.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:52:19 PM | 19 | 1403.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:52:20 PM | 25 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 31 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 64 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 45 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 22 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 2 | 1403.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 73 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 17 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 2 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 32 | 1405.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 22 | 1405.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 6 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 26 | 1404.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 11 | 1403.50 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 23 | 1404.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:52:30 PM | 12 | 1404.50 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:52:31 PM | 22 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:52:31 PM | 25 | 1404.00 | AQEU |
| GENMAB A/S | 27-Mar-25 | 4:52:32 PM | 18 | 1404.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:52:43 PM | 51 | 1404.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:52:50 PM | 12 | 1404.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:53:16 PM | 10 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:18 PM | 17 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:35 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:35 PM | 4 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:35 PM | 2 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:35 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:35 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:35 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:35 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:35 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:36 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:36 PM | 4 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:36 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:38 PM | 4 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:38 PM | 4 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:38 PM | 4 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:38 PM | 36 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:39 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:39 PM | 5 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:39 PM | 4 | 1404.50 | CEUX |
142
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 27-Mar-25 | 4:53:49 PM | 8 | 1403.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 27-Mar-25 | 4:53:57 PM | 10 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:53:57 PM | 10 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:54:03 PM | 17 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:54:10 PM | 41 | 1404.00 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:54:13 PM | 19 | 1404.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:54:13 PM | 10 | 1404.00 | TQEX |
| GENMAB A/S | 27-Mar-25 | 4:54:21 PM | 45 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:21 PM | 8 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:21 PM | 10 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:21 PM | 10 | 1404.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:29 PM | 78 | 1404.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:37 PM | 10 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:37 PM | 1 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:37 PM | 9 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:37 PM | 9 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:37 PM | 45 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:37 PM | 14 | 1404.50 | CEUX |
| GENMAB A/S | 27-Mar-25 | 4:54:38 PM | 10 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:38 PM | 17 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:38 PM | 45 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:38 PM | 8 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:38 PM | 10 | 1405.00 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:52 PM | 28 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 11 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 30 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 10 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 9 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 9 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 30 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 10 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 8 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 9 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 8 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:53 PM | 30 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:54 PM | 10 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:54 PM | 9 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:54 PM | 9 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:56 PM | 30 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:56 PM | 9 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:56 PM | 9 | 1405.50 | XCSE |
| GENMAB A/S | 27-Mar-25 | 4:54:56 PM | 10 | 1405.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:09:21 AM | 16 | 1387.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:10:35 AM | 62 | 1386.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:10:35 AM | 64 | 1387.00 | XCSE |
143
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 10:10:35 AM | 73 | 1386.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 10:10:35 AM | 50 | 1387.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:10:35 AM | 64 | 1386.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:10:35 AM | 71 | 1386.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:10:35 AM | 49 | 1385.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:10:35 AM | 21 | 1385.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:12:11 AM | 59 | 1387.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:12:11 AM | 8 | 1387.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:12:11 AM | 14 | 1387.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:21:09 AM | 36 | 1388.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:21:09 AM | 25 | 1388.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:21:09 AM | 79 | 1388.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:21:09 AM | 25 | 1388.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:21:09 AM | 22 | 1388.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:21:10 AM | 17 | 1389.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:21:13 AM | 10 | 1389.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:22:43 AM | 55 | 1389.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:22:43 AM | 23 | 1389.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:22:43 AM | 36 | 1389.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:22:45 AM | 34 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:22:45 AM | 15 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:22:54 AM | 41 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:22:54 AM | 11 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:22:54 AM | 30 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:24:35 AM | 36 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:25:32 AM | 1 | 1389.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:32 AM | 73 | 1389.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:32 AM | 28 | 1389.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 20 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 53 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 26 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 12 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 21 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 41 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 28 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 32 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:25:39 AM | 15 | 1389.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:25:40 AM | 58 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:26:12 AM | 41 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:26:12 AM | 26 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:26:12 AM | 30 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:26:12 AM | 36 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:26:28 AM | 26 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:26:28 AM | 41 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:26:28 AM | 30 | 1390.00 | XCSE |
144
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 10:26:28 AM | 4 | 1390.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 10:26:28 AM | 24 | 1389.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:26:29 AM | 79 | 1389.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:26:29 AM | 5 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:26:29 AM | 5 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:26:29 AM | 17 | 1389.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:26:29 AM | 14 | 1389.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:26:38 AM | 10 | 1390.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:26:38 AM | 13 | 1390.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:26:38 AM | 43 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:26:43 AM | 22 | 1390.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:27:44 AM | 54 | 1391.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:27:44 AM | 34 | 1391.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:27:44 AM | 13 | 1391.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:27:44 AM | 33 | 1391.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:27:45 AM | 28 | 1391.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:28:46 AM | 43 | 1392.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:28:46 AM | 41 | 1392.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:28:46 AM | 78 | 1392.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:28:46 AM | 17 | 1392.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:28:46 AM | 80 | 1392.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:28:46 AM | 24 | 1392.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:29:45 AM | 17 | 1393.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:29:45 AM | 41 | 1393.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:29:45 AM | 43 | 1393.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:29:45 AM | 32 | 1392.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:29:45 AM | 26 | 1392.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:29:49 AM | 76 | 1392.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:29:49 AM | 61 | 1392.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:29:49 AM | 14 | 1392.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:29:49 AM | 66 | 1392.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:29:51 AM | 45 | 1392.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:29:51 AM | 14 | 1392.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:30:05 AM | 78 | 1392.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:30:05 AM | 17 | 1392.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:30:05 AM | 62 | 1392.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:30:19 AM | 30 | 1391.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:30:19 AM | 41 | 1391.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:30:19 AM | 16 | 1391.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:30:20 AM | 79 | 1391.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:30:20 AM | 76 | 1391.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:31:38 AM | 79 | 1390.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:31:38 AM | 75 | 1390.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:32:12 AM | 29 | 1389.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:32:24 AM | 76 | 1388.50 | XCSE |
145
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 10:32:24 AM | 76 | 1388.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 10:32:25 AM | 2 | 1387.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:32:25 AM | 77 | 1387.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:32:26 AM | 45 | 1387.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:32:28 AM | 11 | 1387.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:32:30 AM | 74 | 1386.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:32:30 AM | 12 | 1385.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:32:30 AM | 35 | 1385.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:33:05 AM | 14 | 1384.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:33:12 AM | 6 | 1385.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:33:35 AM | 77 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:33:35 AM | 25 | 1386.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:33:35 AM | 3 | 1386.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:35:26 AM | 74 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:36:00 AM | 76 | 1385.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:36:00 AM | 25 | 1385.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:37:31 AM | 33 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:37:31 AM | 17 | 1386.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:38:57 AM | 52 | 1386.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:40:02 AM | 30 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:40:02 AM | 80 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:40:02 AM | 41 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:40:02 AM | 12 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:40:02 AM | 73 | 1386.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:40:02 AM | 27 | 1386.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:40:02 AM | 22 | 1386.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:40:03 AM | 18 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:40:03 AM | 43 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:40:37 AM | 50 | 1387.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:44:41 AM | 26 | 1387.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:44:41 AM | 55 | 1387.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:44:41 AM | 13 | 1387.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:44:41 AM | 23 | 1387.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:44:52 AM | 13 | 1387.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:44:52 AM | 7 | 1387.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 12 | 1386.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 41 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 30 | 1387.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 53 | 1386.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 7 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 11 | 1386.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 18 | 1387.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 13 | 1386.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 12 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 30 | 1386.00 | XCSE |
146
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 79 | 1386.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 35 | 1386.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 41 | 1386.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 56 | 1385.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 58 | 1386.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 5 | 1386.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:45:50 AM | 26 | 1386.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:45:51 AM | 23 | 1385.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:46:02 AM | 27 | 1385.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:46:02 AM | 30 | 1385.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:46:14 AM | 15 | 1385.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:46:44 AM | 10 | 1384.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:46:44 AM | 58 | 1384.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:46:44 AM | 29 | 1385.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:46:44 AM | 1 | 1385.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:47:06 AM | 9 | 1384.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:48:07 AM | 24 | 1384.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:48:10 AM | 12 | 1384.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:48:10 AM | 41 | 1384.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:48:21 AM | 41 | 1384.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:48:21 AM | 6 | 1384.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:48:41 AM | 77 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:48:41 AM | 64 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:48:41 AM | 16 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:48:41 AM | 23 | 1383.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:48:41 AM | 38 | 1383.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:49:21 AM | 74 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:49:21 AM | 9 | 1382.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:49:21 AM | 20 | 1382.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:49:26 AM | 24 | 1382.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:51:01 AM | 27 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:51:01 AM | 19 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:51:01 AM | 14 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:51:01 AM | 41 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:51:01 AM | 4 | 1382.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:51:24 AM | 77 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:51:24 AM | 59 | 1381.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:51:24 AM | 15 | 1381.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:51:24 AM | 23 | 1381.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:51:24 AM | 24 | 1381.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:52:02 AM | 76 | 1380.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:52:02 AM | 13 | 1380.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:52:02 AM | 25 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:52:02 AM | 66 | 1380.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:52:02 AM | 2 | 1380.00 | AQEU |
147
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 10:52:10 AM | 51 | 1381.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 10:54:31 AM | 37 | 1382.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:54:31 AM | 36 | 1382.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:54:31 AM | 15 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:54:31 AM | 9 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:54:31 AM | 50 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:57:47 AM | 13 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:47 AM | 41 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:47 AM | 41 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:47 AM | 11 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:47 AM | 11 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:47 AM | 12 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:48 AM | 11 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:48 AM | 12 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:48 AM | 41 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:50 AM | 41 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:50 AM | 11 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:50 AM | 41 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:50 AM | 11 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:50 AM | 38 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:50 AM | 30 | 1383.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:57:50 AM | 78 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:57:50 AM | 16 | 1382.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:58:09 AM | 78 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:58:09 AM | 26 | 1382.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 10:58:09 AM | 15 | 1382.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:59:21 AM | 77 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 10:59:21 AM | 32 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:59:21 AM | 26 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 10:59:21 AM | 14 | 1381.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 10:59:21 AM | 8 | 1381.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:00:37 AM | 13 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:00:37 AM | 18 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:00:37 AM | 74 | 1380.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:00:37 AM | 22 | 1380.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:00:57 AM | 2 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:00:57 AM | 14 | 1380.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:03:27 AM | 22 | 1382.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:04:01 AM | 40 | 1381.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:04:01 AM | 40 | 1381.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:04:01 AM | 75 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:05:47 AM | 4 | 1380.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:06:28 AM | 37 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:06:28 AM | 11 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:06:28 AM | 10 | 1381.50 | CEUX |
148
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 11:06:51 AM | 22 | 1381.00 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 11:06:51 AM | 15 | 1381.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:06:52 AM | 72 | 1380.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:06:52 AM | 19 | 1381.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:07:11 AM | 8 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:07:11 AM | 3 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:09:59 AM | 8 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:10:09 AM | 71 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:10:09 AM | 15 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:11:49 AM | 41 | 1382.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:11:49 AM | 1 | 1382.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:11:51 AM | 20 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:00 AM | 59 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:04 AM | 31 | 1382.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:13:07 AM | 23 | 1382.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:07 AM | 25 | 1382.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:13:11 AM | 12 | 1382.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:11 AM | 32 | 1382.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:11 AM | 73 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:11 AM | 28 | 1382.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:11 AM | 1 | 1382.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:13:11 AM | 34 | 1382.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:13:19 AM | 101 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:19 AM | 78 | 1381.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:19 AM | 65 | 1381.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:19 AM | 23 | 1381.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:13:19 AM | 6 | 1381.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:13:19 AM | 20 | 1381.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:13:20 AM | 101 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:20 AM | 42 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:20 AM | 101 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:20 AM | 59 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:20 AM | 9 | 1380.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:21 AM | 101 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:21 AM | 101 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:22 AM | 9 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:22 AM | 92 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:22 AM | 101 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:23 AM | 3 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:23 AM | 62 | 1381.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:32 AM | 77 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:32 AM | 80 | 1380.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:13:32 AM | 34 | 1380.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:32 AM | 33 | 1380.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:32 AM | 8 | 1380.00 | AQEU |
149
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 11:13:43 AM | 74 | 1378.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 11:13:43 AM | 20 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:43 AM | 57 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:13:45 AM | 22 | 1378.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:14:23 AM | 10 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:14:23 AM | 69 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:15:58 AM | 20 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:16:00 AM | 17 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:16:21 AM | 1 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:16:21 AM | 13 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:16:38 AM | 16 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:16:51 AM | 41 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:16:51 AM | 11 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:16:51 AM | 12 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:17:17 AM | 75 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:18:20 AM | 17 | 1377.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:18:26 AM | 59 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:18:26 AM | 30 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:18:26 AM | 5 | 1377.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:18:45 AM | 25 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:18:45 AM | 3 | 1377.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:18:53 AM | 53 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:18:53 AM | 19 | 1377.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:19:04 AM | 45 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:19:04 AM | 15 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:20:00 AM | 21 | 1376.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:20:01 AM | 9 | 1377.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:20:01 AM | 61 | 1377.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:21:14 AM | 3 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:21:15 AM | 18 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:21:15 AM | 41 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:21:15 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:21:39 AM | 25 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:21:39 AM | 8 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:21:39 AM | 38 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:23:33 AM | 52 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:23:33 AM | 49 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:23:33 AM | 11 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:23:33 AM | 20 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:23:52 AM | 41 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:23:52 AM | 13 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:23:52 AM | 13 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:23:53 AM | 11 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:23:53 AM | 33 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:23:53 AM | 26 | 1378.50 | XCSE |
150
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 11:24:37 AM | 45 | 1377.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 11:25:57 AM | 35 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:25:57 AM | 36 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:25:58 AM | 1 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:26:42 AM | 41 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:26:42 AM | 41 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:26:42 AM | 11 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:26:42 AM | 31 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:28:06 AM | 76 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:28:06 AM | 41 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:28:06 AM | 14 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:28:06 AM | 66 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:28:06 AM | 32 | 1378.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:28:06 AM | 39 | 1378.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:28:47 AM | 27 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:29:08 AM | 34 | 1379.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:29:18 AM | 36 | 1379.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:30:28 AM | 75 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:30:28 AM | 28 | 1379.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:30:30 AM | 41 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:30:30 AM | 23 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:30:30 AM | 1 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:31:58 AM | 10 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:31:58 AM | 7 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:31:58 AM | 5 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:31:59 AM | 1 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:31:59 AM | 33 | 1378.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:32:00 AM | 77 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:32:00 AM | 5 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:32:00 AM | 44 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:32:00 AM | 30 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:32:00 AM | 22 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:32:58 AM | 26 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:32:58 AM | 44 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:33:21 AM | 14 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:33:22 AM | 41 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:33:22 AM | 11 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:33:27 AM | 26 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:34:17 AM | 52 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:34:46 AM | 15 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:34:46 AM | 25 | 1379.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:35:08 AM | 68 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:35:08 AM | 11 | 1379.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:35:08 AM | 32 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:35:10 AM | 41 | 1379.00 | XCSE |
151
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 11:35:52 AM | 11 | 1379.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 11:36:37 AM | 24 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:36:37 AM | 36 | 1379.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:36:47 AM | 41 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:47 AM | 31 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:47 AM | 13 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:47 AM | 12 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:47 AM | 17 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:47 AM | 12 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:47 AM | 41 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:48 AM | 27 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:48 AM | 41 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:48 AM | 30 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:48 AM | 13 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:48 AM | 41 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:48 AM | 19 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:36:48 AM | 11 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:37:21 AM | 13 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:37:21 AM | 37 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:37:55 AM | 10 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:37:55 AM | 12 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:37:55 AM | 13 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:38:19 AM | 9 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:38:19 AM | 13 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:38:43 AM | 12 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:38:43 AM | 41 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:38:43 AM | 31 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:38:50 AM | 16 | 1379.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:38:57 AM | 34 | 1379.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:39:03 AM | 32 | 1379.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:39:16 AM | 32 | 1379.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:40:12 AM | 26 | 1379.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:40:22 AM | 44 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:40:22 AM | 77 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:40:22 AM | 50 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:40:22 AM | 10 | 1379.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:40:22 AM | 69 | 1379.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:40:22 AM | 39 | 1379.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:42:16 AM | 5 | 1380.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:42:16 AM | 80 | 1381.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:44:27 AM | 18 | 1380.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:44:27 AM | 73 | 1380.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:44:27 AM | 22 | 1380.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:44:27 AM | 22 | 1380.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:44:28 AM | 43 | 1380.50 | XCSE |
152
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 11:44:38 AM | 3 | 1380.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 11:44:38 AM | 53 | 1380.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:45:05 AM | 59 | 1380.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:45:05 AM | 20 | 1380.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:45:37 AM | 22 | 1380.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:45:37 AM | 1 | 1380.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:46:46 AM | 12 | 1380.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:47:13 AM | 25 | 1380.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 11:47:21 AM | 79 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:47:34 AM | 24 | 1379.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:47:44 AM | 23 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:47:44 AM | 11 | 1379.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:47:55 AM | 14 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:48:30 AM | 14 | 1378.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:48:47 AM | 58 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:49:57 AM | 22 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:52:34 AM | 21 | 1378.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:52:34 AM | 28 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:52:35 AM | 14 | 1378.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:52:35 AM | 8 | 1378.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:54:27 AM | 74 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:54:27 AM | 36 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:54:27 AM | 23 | 1377.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 11:54:28 AM | 8 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:54:28 AM | 31 | 1377.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:54:28 AM | 36 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:54:29 AM | 26 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:54:29 AM | 43 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:54:29 AM | 1 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:54:29 AM | 53 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:56:17 AM | 12 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:56:17 AM | 14 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:56:51 AM | 16 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:56:51 AM | 17 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:56:51 AM | 12 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:56:51 AM | 30 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:56:52 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:56:52 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:56:53 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:56:57 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:56:59 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:00 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:10 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:15 AM | 37 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:15 AM | 13 | 1378.00 | XCSE |
153
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 11:57:15 AM | 11 | 1378.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 11:57:15 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:15 AM | 37 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:15 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:15 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:15 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:16 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:16 AM | 37 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:16 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:16 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:16 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:16 AM | 37 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:16 AM | 14 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:57:17 AM | 37 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:17 AM | 30 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:17 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:17 AM | 37 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:17 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:17 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:18 AM | 37 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:18 AM | 13 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:18 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:18 AM | 35 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:57:29 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:29 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:55 AM | 31 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:55 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:56 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:56 AM | 11 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:56 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:56 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:56 AM | 12 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:57:57 AM | 12 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:57:59 AM | 7 | 1378.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:59:40 AM | 46 | 1377.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 11:59:40 AM | 79 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 11:59:46 AM | 6 | 1378.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:27 PM | 20 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:28 PM | 44 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:28 PM | 1 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 14 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 41 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 10 | 1376.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 13 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 15 | 1376.50 | XCSE |
154
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 9 | 1377.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 13 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 12 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 9 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 79 | 1376.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 41 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 4 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 30 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 16 | 1377.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 36 | 1377.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 20 | 1377.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 44 | 1376.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 34 | 1376.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 5 | 1377.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 5 | 1377.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 11 | 1376.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:02:46 PM | 15 | 1376.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:02:47 PM | 18 | 1376.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:02:47 PM | 19 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:55 PM | 33 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:02:55 PM | 22 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:03:35 PM | 41 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:03:35 PM | 78 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:03:35 PM | 15 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:03:35 PM | 12 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:03:35 PM | 28 | 1375.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:03:37 PM | 23 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:03:37 PM | 54 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:03:38 PM | 35 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:03:38 PM | 33 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:03:38 PM | 43 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:03:38 PM | 44 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:03:38 PM | 27 | 1374.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:06:43 PM | 77 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:08:25 PM | 23 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:09:07 PM | 55 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:09:13 PM | 30 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:09:13 PM | 29 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:09:37 PM | 50 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:10:46 PM | 10 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:10:46 PM | 20 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:10:46 PM | 34 | 1375.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:11:17 PM | 14 | 1375.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:11:45 PM | 29 | 1375.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:11:58 PM | 32 | 1375.00 | TQEX |
155
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 12:12:10 PM | 2 | 1375.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 12:12:10 PM | 25 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:10 PM | 41 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:10 PM | 8 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:10 PM | 3 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:10 PM | 30 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:12 PM | 4 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:12 PM | 13 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:47 PM | 23 | 1374.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:12:48 PM | 32 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:48 PM | 11 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:48 PM | 39 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:48 PM | 11 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:48 PM | 15 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:12:49 PM | 13 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:49 PM | 12 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:49 PM | 41 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:49 PM | 11 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:49 PM | 13 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:49 PM | 32 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:50 PM | 11 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:50 PM | 10 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:50 PM | 13 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:50 PM | 13 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:50 PM | 13 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:51 PM | 5 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:51 PM | 12 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:12:51 PM | 28 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 16 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 58 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 75 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 61 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 10 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 70 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 79 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 27 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 3 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 22 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 23 | 1373.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 18 | 1372.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:13:03 PM | 4 | 1372.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:13:04 PM | 15 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:13:04 PM | 18 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:13:18 PM | 44 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:13:18 PM | 24 | 1371.50 | TQEX |
156
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 12:14:23 PM | 3 | 1371.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 12:18:22 PM | 44 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 5 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 11 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 12 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 30 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 30 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 35 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 12 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 24 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:47 PM | 43 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:48 PM | 74 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:48 PM | 74 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:18:48 PM | 6 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:18:48 PM | 77 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:18:48 PM | 55 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:18:48 PM | 31 | 1370.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:19:10 PM | 8 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:19:10 PM | 60 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:20:42 PM | 75 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:24:21 PM | 53 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:24:21 PM | 1 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:24:21 PM | 6 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:24:21 PM | 9 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:25:21 PM | 11 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:25:21 PM | 19 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:25:21 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:26:10 PM | 11 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:26:10 PM | 22 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:26:57 PM | 42 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:32:27 PM | 1 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:32:27 PM | 53 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:32:27 PM | 16 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:32:27 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:32:28 PM | 11 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:32:39 PM | 12 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:32:39 PM | 48 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:32:39 PM | 39 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:32:53 PM | 12 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:32:53 PM | 46 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:32:53 PM | 43 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:34:17 PM | 32 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:34:17 PM | 77 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:34:17 PM | 14 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:34:17 PM | 25 | 1372.50 | TQEX |
157
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 12:34:44 PM | 15 | 1372.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 12:34:44 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 42 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 22 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 30 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 50 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 32 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 30 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 21 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 16 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:33 PM | 4 | 1372.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:35:34 PM | 2 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:34 PM | 8 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:34 PM | 12 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:34 PM | 11 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:34 PM | 1 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:35 PM | 12 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:35 PM | 11 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:35 PM | 30 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:35 PM | 30 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:36 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:36 PM | 2 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:36 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:36 PM | 37 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:35:36 PM | 30 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:36:27 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:36:27 PM | 42 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:36:27 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:36:27 PM | 32 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:37:11 PM | 11 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:37:11 PM | 11 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:37:11 PM | 32 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:38:00 PM | 2 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:38:24 PM | 96 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:38:28 PM | 4 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:38:28 PM | 59 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:38:32 PM | 10 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:39:21 PM | 74 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:39:21 PM | 1 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:41:44 PM | 25 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:41:44 PM | 5 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:41:44 PM | 70 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:41:44 PM | 44 | 1374.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:41:44 PM | 22 | 1374.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:41:45 PM | 1 | 1374.50 | XCSE |
158
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 12:41:45 PM | 1 | 1374.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 12:42:28 PM | 36 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:43:00 PM | 10 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:45:47 PM | 78 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:48:15 PM | 1 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:48:15 PM | 36 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:48:17 PM | 6 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:48:28 PM | 5 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:48:35 PM | 10 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:48:37 PM | 35 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:48:37 PM | 25 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:48:37 PM | 10 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:48:37 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:48:37 PM | 3 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:48:38 PM | 1 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:50:00 PM | 10 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:50:30 PM | 5 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:50:30 PM | 5 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:50:43 PM | 1 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:00 PM | 10 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:18 PM | 6 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:18 PM | 6 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:18 PM | 5 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:45 PM | 6 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:45 PM | 6 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:45 PM | 6 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:45 PM | 6 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:52 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:52 PM | 41 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:52 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:53 PM | 12 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:53 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:54 PM | 7 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:54 PM | 12 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:54 PM | 12 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:55 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:55 PM | 10 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:55 PM | 30 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:55 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:56 PM | 30 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:56 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:56 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 74 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 16 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 30 | 1374.00 | XCSE |
159
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 42 | 1374.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 70 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 35 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 36 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 30 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 45 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:51:59 PM | 25 | 1373.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:52:00 PM | 49 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:00 PM | 11 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:00 PM | 36 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:52:00 PM | 6 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:52:00 PM | 6 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:52:00 PM | 34 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:52:02 PM | 3 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:02 PM | 42 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:04 PM | 2 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:04 PM | 30 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:04 PM | 42 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:14 PM | 77 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:14 PM | 101 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:14 PM | 79 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:52:14 PM | 37 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:52:14 PM | 19 | 1372.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:52:33 PM | 76 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:33 PM | 45 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:52:33 PM | 34 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:52:33 PM | 32 | 1371.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:52:36 PM | 79 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:52:36 PM | 42 | 1370.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:52:36 PM | 28 | 1370.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 12:52:38 PM | 46 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:52:38 PM | 30 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:54:59 PM | 34 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:54:59 PM | 26 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:55:00 PM | 30 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:55:00 PM | 8 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:55:00 PM | 9 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:55:00 PM | 3 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:55:00 PM | 15 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 12:55:00 PM | 16 | 1370.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 12:57:17 PM | 79 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:57:17 PM | 1 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:57:17 PM | 9 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:57:17 PM | 42 | 1370.00 | XCSE |
160
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 12:57:17 PM | 10 | 1370.00 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 12:57:45 PM | 26 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:57:45 PM | 10 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:57:46 PM | 11 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 12:57:48 PM | 58 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:00:07 PM | 78 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:01:17 PM | 72 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:02:46 PM | 42 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:02:46 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:02:46 PM | 4 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:02:46 PM | 44 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:02:46 PM | 35 | 1369.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:05:17 PM | 12 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:05:18 PM | 33 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:05:18 PM | 38 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:05:29 PM | 6 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:05:43 PM | 32 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:06:13 PM | 32 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:06:35 PM | 11 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:06:35 PM | 42 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:06:35 PM | 5 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:06:35 PM | 16 | 1369.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:06:35 PM | 6 | 1369.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:06:36 PM | 15 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:06:36 PM | 19 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:06:36 PM | 42 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 9 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 12 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 25 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 32 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 42 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 16 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 11 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 7 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 6 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 6 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 78 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 11 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 42 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 18 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:16 PM | 3 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:37 PM | 32 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:38 PM | 33 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:38 PM | 4 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:07:51 PM | 12 | 1369.00 | XCSE |
161
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 1:07:51 PM | 13 | 1369.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 1:07:54 PM | 4 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:08:21 PM | 42 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:08:21 PM | 43 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:08:21 PM | 13 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:08:21 PM | 1 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:08:38 PM | 32 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:08:57 PM | 14 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:08:57 PM | 13 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:09:28 PM | 28 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:09:28 PM | 12 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:09:28 PM | 32 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:09:28 PM | 30 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:11:19 PM | 77 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:11:19 PM | 24 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:11:19 PM | 79 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:14:17 PM | 60 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:14:17 PM | 41 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:14:17 PM | 25 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:16:27 PM | 74 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:16:28 PM | 15 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:16:28 PM | 1 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:16:28 PM | 48 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:16:28 PM | 35 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:16:31 PM | 9 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:16:31 PM | 48 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:16:31 PM | 44 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:16:31 PM | 79 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:16:31 PM | 42 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:16:58 PM | 10 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:17:18 PM | 9 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:17:18 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:17:18 PM | 32 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:17:39 PM | 10 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:17:39 PM | 32 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:17:39 PM | 45 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:17:39 PM | 79 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:17:39 PM | 14 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:17:39 PM | 78 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:17:39 PM | 30 | 1367.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:17:40 PM | 77 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:17:41 PM | 9 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:18:47 PM | 69 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:18:47 PM | 29 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:20:10 PM | 54 | 1366.50 | CEUX |
162
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 1:20:10 PM | 22 | 1366.50 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 1:20:10 PM | 22 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:20:11 PM | 75 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:20:11 PM | 76 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:20:11 PM | 25 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:20:13 PM | 22 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:23:39 PM | 48 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:23:39 PM | 30 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:23:39 PM | 1 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:23:45 PM | 8 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:24:35 PM | 78 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:24:35 PM | 28 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:24:40 PM | 18 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:24:40 PM | 25 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:24:41 PM | 20 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:24:42 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:24:42 PM | 48 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:25:08 PM | 48 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:25:08 PM | 1 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:25:08 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:25:08 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:25:19 PM | 79 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:26:26 PM | 13 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:26:26 PM | 9 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:26:31 PM | 31 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:26:51 PM | 1 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:26:51 PM | 4 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:27:46 PM | 20 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:27:46 PM | 34 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:27:46 PM | 11 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:27:46 PM | 24 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:27:46 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:27:50 PM | 31 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:27:50 PM | 43 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:27:52 PM | 20 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:28:43 PM | 34 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:28:43 PM | 18 | 1363.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:28:43 PM | 4 | 1363.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:30:26 PM | 11 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:30:26 PM | 1 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:30:27 PM | 25 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:30:27 PM | 46 | 1363.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:30:27 PM | 32 | 1363.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:30:29 PM | 1 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:30:37 PM | 5 | 1362.50 | XCSE |
163
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 1:30:37 PM | 45 | 1362.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 1:30:37 PM | 23 | 1362.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:30:37 PM | 1 | 1362.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:30:53 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:30:54 PM | 11 | 1363.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:32:14 PM | 27 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:32:19 PM | 32 | 1363.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:32:25 PM | 83 | 1363.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:32:25 PM | 48 | 1363.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:32:26 PM | 13 | 1363.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:03 PM | 12 | 1362.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:03 PM | 47 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:03 PM | 41 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:03 PM | 48 | 1362.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:03 PM | 11 | 1361.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:34:03 PM | 75 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:34:03 PM | 12 | 1361.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:34:31 PM | 9 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:31 PM | 13 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:41 PM | 13 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:41 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:34:41 PM | 8 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:35:28 PM | 14 | 1362.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:37:08 PM | 13 | 1361.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:08 PM | 48 | 1361.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:08 PM | 76 | 1361.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:08 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:08 PM | 18 | 1361.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:37:08 PM | 34 | 1361.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:37:08 PM | 24 | 1360.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:37:09 PM | 12 | 1361.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:37:23 PM | 13 | 1361.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:23 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:23 PM | 11 | 1361.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:23 PM | 30 | 1361.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:37:23 PM | 32 | 1361.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:37:46 PM | 65 | 1362.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:46 PM | 12 | 1362.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:37:46 PM | 14 | 1362.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:37:46 PM | 8 | 1362.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:38:53 PM | 79 | 1362.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:38:53 PM | 32 | 1361.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:38:53 PM | 47 | 1361.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:38:53 PM | 80 | 1361.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:38:53 PM | 22 | 1362.00 | TQEX |
164
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 1:38:53 PM | 23 | 1361.00 | AQEU |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 1:38:53 PM | 28 | 1362.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:40:54 PM | 12 | 1361.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:40:54 PM | 36 | 1361.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:40:54 PM | 13 | 1361.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:40:54 PM | 1 | 1361.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:40:54 PM | 39 | 1361.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:42:37 PM | 23 | 1362.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:43:00 PM | 34 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:43:00 PM | 44 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:43:00 PM | 25 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:43:00 PM | 12 | 1362.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:43:25 PM | 29 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:43:26 PM | 13 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:43:26 PM | 43 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:43:26 PM | 7 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:43:26 PM | 16 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:43:26 PM | 10 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:43:26 PM | 22 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:43:38 PM | 26 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:43:41 PM | 12 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:43:41 PM | 43 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:43:41 PM | 6 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:44:18 PM | 3 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:44:18 PM | 12 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:44:18 PM | 2 | 1362.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:44:25 PM | 1 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:44:25 PM | 2 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:44:25 PM | 1 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:44:45 PM | 12 | 1363.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:44:45 PM | 8 | 1363.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:44:51 PM | 10 | 1363.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:45:26 PM | 5 | 1363.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:05 PM | 31 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:05 PM | 12 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:05 PM | 13 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:05 PM | 2 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:05 PM | 9 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:06 PM | 14 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:06 PM | 8 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:06 PM | 12 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:06 PM | 1 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:06 PM | 1 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:21 PM | 11 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:21 PM | 11 | 1363.50 | XCSE |
165
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 1:46:41 PM | 12 | 1363.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 1:46:41 PM | 9 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:41 PM | 13 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:46:53 PM | 25 | 1362.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:47:16 PM | 5 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:16 PM | 11 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:16 PM | 24 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:16 PM | 6 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:16 PM | 17 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:17 PM | 22 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:17 PM | 17 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:17 PM | 8 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:21 PM | 5 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:47:21 PM | 41 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:47:38 PM | 1 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:47:38 PM | 23 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:48:25 PM | 7 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:48:25 PM | 10 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:49:25 PM | 25 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:50:09 PM | 34 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:50:09 PM | 15 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:50:09 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:50:09 PM | 23 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:50:09 PM | 13 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:53:11 PM | 34 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:53:11 PM | 1 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:53:11 PM | 21 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:53:33 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:53:33 PM | 15 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:53:33 PM | 9 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:53:33 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:53:34 PM | 7 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:54:00 PM | 33 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:54:12 PM | 43 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:54:14 PM | 17 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:54:14 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:54:14 PM | 36 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:54:14 PM | 6 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:54:14 PM | 80 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:54:15 PM | 36 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:54:15 PM | 14 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:54:26 PM | 41 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:54:26 PM | 23 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:54:26 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:54:26 PM | 10 | 1366.00 | XCSE |
166
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 1:54:27 PM | 26 | 1366.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 1:54:27 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:00 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:00 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:00 PM | 1 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:00 PM | 3 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:00 PM | 53 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:00 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:00 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:19 PM | 36 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 19 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 44 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 24 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 51 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 43 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 79 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 3 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 33 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:55:31 PM | 29 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:56:57 PM | 36 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:56:57 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:56:57 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:56:57 PM | 5 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:56:58 PM | 100 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:56:58 PM | 14 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:57:19 PM | 80 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 1:57:41 PM | 8 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:57:41 PM | 41 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:58:46 PM | 76 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 1:58:46 PM | 23 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 1:58:46 PM | 6 | 1364.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 1:58:48 PM | 21 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:00:55 PM | 42 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:00:55 PM | 1 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:00:55 PM | 18 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:00:55 PM | 30 | 1367.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:01:28 PM | 40 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:01:28 PM | 53 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:01:28 PM | 8 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:01:45 PM | 25 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:02:05 PM | 42 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:02:05 PM | 13 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:02:05 PM | 30 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:02:36 PM | 74 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:03:08 PM | 11 | 1367.00 | CEUX |
167
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:03:08 PM | 1 | 1367.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:03:28 PM | 10 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:03:28 PM | 12 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:04:25 PM | 32 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:04:35 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:04:35 PM | 20 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:04:35 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:04:45 PM | 20 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:04:45 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:04:45 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:04:45 PM | 78 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:04:45 PM | 27 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:05:12 PM | 30 | 1366.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:05:21 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:05:21 PM | 31 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:05:51 PM | 23 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:05:51 PM | 1 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:05:51 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:05:51 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:05:51 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 75 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 34 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 78 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 74 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 20 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 14 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 24 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 2 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 23 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 2 | 1364.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 2 | 1366.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 23 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:06:41 PM | 29 | 1364.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:07:46 PM | 4 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:08:37 PM | 34 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:08:37 PM | 43 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:09:47 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:09:47 PM | 22 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:09:47 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:04 PM | 72 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:11:04 PM | 4 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:11:04 PM | 29 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:11:04 PM | 29 | 1366.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:11:05 PM | 44 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:31 PM | 23 | 1367.00 | XCSE |
168
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:11:31 PM | 1 | 1367.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:11:31 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:31 PM | 14 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:31 PM | 24 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:32 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:32 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:32 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:32 PM | 24 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:11:32 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:12:11 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:12:11 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:13:25 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:13:25 PM | 32 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 2 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 26 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 75 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 80 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 23 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:13:58 PM | 29 | 1366.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:14:13 PM | 20 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:14:13 PM | 43 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:14:51 PM | 47 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:15:25 PM | 21 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:15:25 PM | 1 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:15:41 PM | 43 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:15:41 PM | 6 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:15:41 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:16:00 PM | 21 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:16:00 PM | 55 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:16:25 PM | 3 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:16:26 PM | 14 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:16:47 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:16:47 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:16:47 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:17:01 PM | 74 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:17:04 PM | 22 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:17:28 PM | 9 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:17:28 PM | 56 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:17:28 PM | 36 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:17:50 PM | 26 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:17:50 PM | 52 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:18:25 PM | 11 | 1366.00 | XCSE |
169
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:18:25 PM | 24 | 1366.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:18:25 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:18:27 PM | 37 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:18:27 PM | 20 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:18:27 PM | 79 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:18:27 PM | 65 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:18:27 PM | 14 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:18:27 PM | 30 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:18:27 PM | 22 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:18:37 PM | 44 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:18:37 PM | 10 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:18:37 PM | 27 | 1364.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:18:39 PM | 34 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:19:09 PM | 6 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:19:16 PM | 76 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:19:16 PM | 22 | 1363.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:22:27 PM | 74 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:23:25 PM | 46 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:23:25 PM | 34 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:23:43 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:23:43 PM | 67 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:23:43 PM | 78 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:23:43 PM | 31 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:23:43 PM | 17 | 1367.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:23:43 PM | 3 | 1367.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:23:43 PM | 7 | 1367.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:24:00 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:24:30 PM | 14 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:24:30 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:24:30 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:25:26 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:25:48 PM | 12 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:25:48 PM | 10 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:25:48 PM | 5 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:25:48 PM | 29 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:26:17 PM | 79 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:26:23 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:26:23 PM | 14 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 32 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 5 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 29 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 37 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 30 | 1367.50 | CEUX |
170
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 41 | 1367.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 5 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 34 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 22 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:27:50 PM | 22 | 1367.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:28:25 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:25 PM | 76 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:25 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:25 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:25 PM | 10 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:28:41 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:41 PM | 29 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:41 PM | 30 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:41 PM | 25 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:28:41 PM | 14 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:28:44 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:44 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:44 PM | 21 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:44 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:28:48 PM | 32 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:29:05 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:29:05 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 10 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 7 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 42 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 26 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 16 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 10 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 30 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 34 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 5 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 11 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 2 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:30:00 PM | 10 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:30:01 PM | 101 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:20 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:20 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:20 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:20 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:20 PM | 3 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:20 PM | 5 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:29 PM | 16 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:29 PM | 12 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:29 PM | 7 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:29 PM | 12 | 1368.50 | XCSE |
171
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:30:29 PM | 42 | 1368.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:30:37 PM | 30 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:37 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:38 PM | 5 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:38 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:38 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:38 PM | 10 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:38 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:30:38 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:31:12 PM | 75 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:31:12 PM | 75 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:31:12 PM | 36 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:31:12 PM | 10 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:31:12 PM | 11 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:31:12 PM | 33 | 1370.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:31:12 PM | 22 | 1370.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:31:16 PM | 42 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:31:16 PM | 20 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:31:16 PM | 36 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:31:16 PM | 2 | 1370.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:31:16 PM | 22 | 1370.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:31:16 PM | 34 | 1370.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:31:26 PM | 2 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:31:31 PM | 46 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:31:31 PM | 24 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:31:47 PM | 20 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:32:17 PM | 62 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:32:17 PM | 14 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:32:17 PM | 15 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:32:17 PM | 36 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:32:25 PM | 18 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:32:49 PM | 44 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:32:49 PM | 80 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:32:49 PM | 3 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:32:49 PM | 36 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:32:49 PM | 29 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:32:49 PM | 48 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:32:49 PM | 22 | 1371.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:32:49 PM | 31 | 1371.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:33:05 PM | 8 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:33:05 PM | 14 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:33:05 PM | 32 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:33:09 PM | 42 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:33:09 PM | 12 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:33:24 PM | 17 | 1371.00 | XCSE |
172
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:33:24 PM | 12 | 1371.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:33:24 PM | 64 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:33:24 PM | 42 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:33:24 PM | 10 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:33:24 PM | 30 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:33:24 PM | 74 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:33:24 PM | 28 | 1370.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:33:27 PM | 79 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:33:40 PM | 78 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:33:59 PM | 30 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:33:59 PM | 25 | 1370.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:34:17 PM | 75 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:34:17 PM | 76 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:34:17 PM | 34 | 1369.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:34:38 PM | 27 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:34:38 PM | 1 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:34:38 PM | 22 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:35:25 PM | 3 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:35:25 PM | 30 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:35:26 PM | 3 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:35:26 PM | 58 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:35:35 PM | 78 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:35:35 PM | 22 | 1369.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 42 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 14 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 50 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 13 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 9 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 13 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 19 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 42 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:42 PM | 76 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:51 PM | 42 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:51 PM | 1 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:51 PM | 18 | 1368.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:35:51 PM | 4 | 1368.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:35:57 PM | 4 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:35:57 PM | 1 | 1368.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:36:01 PM | 75 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:36:01 PM | 80 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:36:12 PM | 25 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:38:27 PM | 62 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:38:32 PM | 35 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:38:33 PM | 30 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:38:33 PM | 14 | 1371.00 | CEUX |
173
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:38:56 PM | 38 | 1372.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:38:56 PM | 10 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:38:56 PM | 13 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:39:19 PM | 38 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:39:19 PM | 15 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:40:47 PM | 36 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:40:47 PM | 78 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:40:47 PM | 26 | 1373.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:41:07 PM | 23 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:41:07 PM | 54 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:41:07 PM | 36 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:41:08 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:41:08 PM | 12 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:41:08 PM | 12 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:41:08 PM | 5 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:41:08 PM | 6 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:41:08 PM | 36 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:41:09 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:41:09 PM | 4 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:41:09 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:41:09 PM | 61 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:42:01 PM | 76 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:42:05 PM | 62 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:42:05 PM | 36 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:42:06 PM | 36 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:42:06 PM | 5 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:42:14 PM | 36 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:42:15 PM | 16 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:42:15 PM | 32 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:42:26 PM | 13 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:42:26 PM | 13 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:42:26 PM | 44 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:42:26 PM | 11 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:42:26 PM | 11 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:42:28 PM | 54 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:43:16 PM | 74 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 78 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 5 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 80 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 39 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 11 | 1371.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 49 | 1372.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 41 | 1371.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 3 | 1371.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:43:22 PM | 11 | 1371.00 | TQEX |
174
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:43:35 PM | 74 | 1373.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:44:50 PM | 24 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:44:58 PM | 60 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:44:58 PM | 19 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:44:58 PM | 75 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:44:58 PM | 77 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:44:58 PM | 23 | 1372.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:44:59 PM | 11 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:44:59 PM | 64 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:44:59 PM | 15 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:00 PM | 15 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:00 PM | 30 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:00 PM | 42 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:00 PM | 6 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:00 PM | 13 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:00 PM | 11 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:00 PM | 12 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:01 PM | 77 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:01 PM | 101 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:01 PM | 30 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:45:01 PM | 22 | 1371.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 11 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 12 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 42 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 22 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 13 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 42 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 16 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 11 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 12 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:02 PM | 13 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:07 PM | 3 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:11 PM | 22 | 1370.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:45:26 PM | 3 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:26 PM | 1 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:29 PM | 101 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:29 PM | 101 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:29 PM | 101 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:30 PM | 101 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:30 PM | 101 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:55 PM | 39 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:55 PM | 4 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:55 PM | 16 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:55 PM | 42 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 12 | 1372.50 | XCSE |
175
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 20 | 1372.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 12 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 16 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 2 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 42 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 11 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 13 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 50 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:45:56 PM | 24 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:46:36 PM | 12 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:46:36 PM | 2 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:46:53 PM | 41 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:46:53 PM | 75 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:46:53 PM | 75 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:46:53 PM | 60 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:46:53 PM | 74 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:46:53 PM | 22 | 1371.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:47:01 PM | 13 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:01 PM | 77 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:01 PM | 50 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:01 PM | 38 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:01 PM | 34 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:47:01 PM | 45 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:47:01 PM | 31 | 1370.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:47:56 PM | 101 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:56 PM | 78 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:56 PM | 21 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:56 PM | 30 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:56 PM | 9 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:56 PM | 41 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:56 PM | 54 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:47:56 PM | 77 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:47:57 PM | 30 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:57 PM | 12 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:57 PM | 13 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:57 PM | 41 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:47:57 PM | 5 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:48:58 PM | 29 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:48:58 PM | 11 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:49:27 PM | 74 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:50:54 PM | 74 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:50:54 PM | 16 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:50:54 PM | 42 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:50:54 PM | 32 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 5 | 1373.50 | XCSE |
176
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 30 | 1373.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 43 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 21 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 50 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 77 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 11 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 42 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:51:07 PM | 76 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:51:08 PM | 8 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:51:08 PM | 17 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:51:08 PM | 12 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:00 PM | 42 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:00 PM | 30 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:00 PM | 42 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:00 PM | 64 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:52:00 PM | 12 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:52:00 PM | 22 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:52:08 PM | 13 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:08 PM | 24 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:08 PM | 12 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:09 PM | 9 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:09 PM | 13 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:09 PM | 77 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:52:09 PM | 22 | 1373.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:52:21 PM | 41 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:41 PM | 14 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:53 PM | 33 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:53 PM | 11 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:53 PM | 42 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:52:53 PM | 12 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:03 PM | 74 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:54:03 PM | 22 | 1374.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:54:04 PM | 4 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:04 PM | 61 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:04 PM | 26 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:04 PM | 40 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:04 PM | 12 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:04 PM | 42 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:04 PM | 11 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:31 PM | 13 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:54:31 PM | 13 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:55:21 PM | 69 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:55:21 PM | 32 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:55:22 PM | 12 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:55:25 PM | 8 | 1374.50 | TQEX |
177
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 2:55:32 PM | 12 | 1374.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 2:56:27 PM | 2 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:56:38 PM | 9 | 1375.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:57:25 PM | 37 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:57:25 PM | 5 | 1375.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:57:25 PM | 18 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:57:25 PM | 10 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:57:25 PM | 20 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:57:25 PM | 13 | 1375.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:57:25 PM | 8 | 1374.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 2:58:13 PM | 25 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:58:13 PM | 53 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:58:13 PM | 8 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:58:25 PM | 29 | 1376.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:58:25 PM | 10 | 1376.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:58:25 PM | 21 | 1376.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:58:40 PM | 40 | 1376.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:59:02 PM | 15 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:59:02 PM | 78 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:59:02 PM | 41 | 1375.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 2:59:25 PM | 2 | 1375.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 2:59:26 PM | 7 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 2:59:59 PM | 10 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 3 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 16 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 9 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 11 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 55 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 11 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 13 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 2 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 1 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 4 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 6 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 7 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 2 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 10 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 69 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 31 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 26 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 38 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 13 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 2 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 20 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 29 | 1373.00 | CEUX |
178
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 3 | 1373.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 7 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 6 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 5 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 3 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 15 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 6 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 16 | 1374.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 8 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 3 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 5 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 2 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 3 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 15 | 1374.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 7 | 1373.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:00:00 PM | 3 | 1373.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:00:25 PM | 5 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:25 PM | 5 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:26 PM | 31 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:28 PM | 1 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:00:28 PM | 4 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:01:03 PM | 78 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:01:03 PM | 80 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:01:03 PM | 31 | 1374.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:01:03 PM | 10 | 1373.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:01:38 PM | 3 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:01:38 PM | 5 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:01:38 PM | 2 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:01:38 PM | 14 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:01:38 PM | 1 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:01:38 PM | 73 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:01:38 PM | 8 | 1373.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:02:17 PM | 54 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:02:26 PM | 10 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:02:26 PM | 17 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:03:12 PM | 76 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:03:12 PM | 36 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:03:12 PM | 6 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:04:07 PM | 80 | 1371.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:17 PM | 14 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:17 PM | 11 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:17 PM | 34 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:17 PM | 42 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 32 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 53 | 1372.00 | XCSE |
179
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 10 | 1372.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 13 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 16 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 11 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 20 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 11 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:18 PM | 12 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:19 PM | 11 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:19 PM | 11 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:19 PM | 20 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:04:28 PM | 14 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:04:28 PM | 7 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:04:28 PM | 29 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:04:28 PM | 12 | 1372.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:06:02 PM | 62 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:06:47 PM | 62 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:07:01 PM | 17 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:07:30 PM | 20 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:07:30 PM | 41 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:07:55 PM | 37 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:07:56 PM | 13 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:07:56 PM | 12 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:07:56 PM | 14 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:07:57 PM | 10 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:07:57 PM | 65 | 1374.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:07:57 PM | 23 | 1374.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:08:00 PM | 40 | 1375.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:08:48 PM | 10 | 1375.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:09:00 PM | 11 | 1375.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:09:47 PM | 36 | 1375.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:13 PM | 40 | 1375.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:13 PM | 1 | 1375.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:13 PM | 15 | 1375.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:13 PM | 58 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:13 PM | 36 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:13 PM | 21 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:13 PM | 15 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:13 PM | 37 | 1375.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:10:14 PM | 10 | 1375.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:42 PM | 76 | 1376.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:42 PM | 28 | 1376.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 38 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 12 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 12 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 13 | 1375.00 | XCSE |
180
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 6 | 1375.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 42 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 38 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 12 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 30 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 12 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 74 | 1374.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 4 | 1375.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 2 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 59 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 6 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 4 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 16 | 1374.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 7 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 31 | 1374.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 20 | 1373.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 20 | 1373.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 25 | 1376.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:10:52 PM | 2 | 1373.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:10:53 PM | 3 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:53 PM | 3 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:53 PM | 53 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:10:53 PM | 1 | 1373.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:11:00 PM | 30 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:00 PM | 42 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:00 PM | 42 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:00 PM | 11 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:00 PM | 11 | 1373.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:00 PM | 77 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:11:18 PM | 5 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 16 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 42 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 19 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 17 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 6 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 30 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 20 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:11:35 PM | 25 | 1373.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 15 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 42 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 15 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 5 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 13 | 1374.00 | XCSE |
181
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 11 | 1374.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 3 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 14 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 42 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 30 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:36 PM | 12 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 9 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 12 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 42 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 4 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 3 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:37 PM | 5 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 2 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 19 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 6 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 42 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 16 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 42 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:55 PM | 23 | 1373.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:11:56 PM | 13 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:56 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:56 PM | 11 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:56 PM | 12 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:11:56 PM | 42 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:03 PM | 2 | 1374.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 60 | 1372.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 8 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 1 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 13 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 66 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 76 | 1372.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 20 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 4 | 1373.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 23 | 1373.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 74 | 1372.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:12:27 PM | 22 | 1372.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:12:55 PM | 64 | 1371.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:12:55 PM | 12 | 1371.50 | CEUX |
182
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:13:10 PM | 80 | 1371.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:13:10 PM | 42 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:13:10 PM | 17 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:13:15 PM | 79 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:13:15 PM | 17 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:13:15 PM | 53 | 1370.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:14:21 PM | 80 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:14:21 PM | 27 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:14:21 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:15:00 PM | 43 | 1370.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:15:28 PM | 2 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:21 PM | 1 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:37 PM | 75 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:37 PM | 1 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:42 PM | 101 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:42 PM | 74 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:16:42 PM | 22 | 1370.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:16:43 PM | 101 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:43 PM | 42 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:43 PM | 59 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:43 PM | 80 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:53 PM | 40 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:16:53 PM | 22 | 1369.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:16:58 PM | 74 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:16:58 PM | 23 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:16:58 PM | 25 | 1368.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:17:10 PM | 12 | 1368.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:17:10 PM | 10 | 1368.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:17:47 PM | 35 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:17:47 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:17:47 PM | 35 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:17:47 PM | 16 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:18:54 PM | 50 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:18:54 PM | 22 | 1368.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:18:56 PM | 15 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:18:56 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:18:56 PM | 30 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:18:56 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:18:56 PM | 80 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:18:56 PM | 14 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:21:12 PM | 73 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:21:12 PM | 2 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:21:12 PM | 75 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:21:12 PM | 22 | 1369.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:21:25 PM | 12 | 1369.50 | XCSE |
183
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:21:26 PM | 6 | 1369.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:22:27 PM | 53 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:22:30 PM | 4 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:23:10 PM | 28 | 1370.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:24:37 PM | 74 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:24:42 PM | 11 | 1370.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:25:10 PM | 30 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:25:10 PM | 11 | 1370.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:25:43 PM | 9 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:25:57 PM | 71 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:25:57 PM | 36 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:25:57 PM | 34 | 1370.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:26:25 PM | 13 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:26:25 PM | 6 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:26:28 PM | 6 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:27:26 PM | 22 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:27:50 PM | 3 | 1371.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:27:50 PM | 11 | 1371.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:28:29 PM | 24 | 1371.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:28:29 PM | 13 | 1371.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:28:38 PM | 61 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:28:38 PM | 15 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:29:26 PM | 12 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:30:43 PM | 34 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:30:43 PM | 16 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:30:47 PM | 20 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 13 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 42 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 22 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 35 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 4 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 44 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 20 | 1370.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 79 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 7 | 1370.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 46 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:30:59 PM | 25 | 1370.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 12 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 11 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 20 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 20 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 12 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 12 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 42 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 12 | 1370.00 | XCSE |
184
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 12 | 1370.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 13 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 21 | 1369.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:31:00 PM | 3 | 1369.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:31:01 PM | 42 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:01 PM | 13 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:01 PM | 19 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:01 PM | 42 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:01 PM | 11 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:01 PM | 13 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:02 PM | 5 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:02 PM | 11 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:22 PM | 12 | 1370.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:30 PM | 31 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:31:30 PM | 45 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:31:30 PM | 27 | 1369.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:31:31 PM | 2 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 30 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 11 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 41 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 36 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 6 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:31:47 PM | 5 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:31:51 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:51 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:51 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:52 PM | 3 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:52 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:52 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:53 PM | 11 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:55 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:55 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:55 PM | 41 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:55 PM | 41 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:55 PM | 12 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 41 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 41 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 41 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 11 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 11 | 1369.50 | XCSE |
185
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 12 | 1369.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:31:56 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:57 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:31:58 PM | 13 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:08 PM | 10 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:32:08 PM | 15 | 1369.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:32:10 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:10 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:11 PM | 11 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:11 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:18 PM | 7 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:32 PM | 52 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:32 PM | 6 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:32 PM | 17 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:32:32 PM | 69 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:32:32 PM | 42 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:33:13 PM | 23 | 1368.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:33:26 PM | 35 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:33:26 PM | 1 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:33:27 PM | 4 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:33:27 PM | 73 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:33:28 PM | 2 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:33:29 PM | 20 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:33:48 PM | 53 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:09 PM | 24 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:09 PM | 78 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 20 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 44 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 25 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 3 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:25 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:34:28 PM | 3 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:28 PM | 11 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:28 PM | 78 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:37 PM | 20 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:37 PM | 3 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:37 PM | 10 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:48 PM | 20 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:48 PM | 20 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:34:51 PM | 4 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:36:00 PM | 36 | 1369.00 | XCSE |
186
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:36:00 PM | 43 | 1369.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:36:15 PM | 4 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:36:15 PM | 1 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:36:20 PM | 75 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:36:28 PM | 12 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:36:28 PM | 65 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:36:28 PM | 11 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:36:28 PM | 13 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:36:28 PM | 39 | 1369.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:37:38 PM | 23 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:37:47 PM | 76 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:18 PM | 75 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:38:18 PM | 5 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:38:31 PM | 50 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:38:31 PM | 24 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:38:38 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:38 PM | 9 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:38 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:39 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:39 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:39 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:39 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:39 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:39 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:40 PM | 33 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:40 PM | 33 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:40 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:40 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:40 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:40 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 33 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 33 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 33 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:41 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:42 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:42 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:42 PM | 33 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:42 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:42 PM | 33 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:42 PM | 33 | 1368.00 | XCSE |
187
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:38:42 PM | 13 | 1368.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:38:51 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:38:51 PM | 8 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:39:11 PM | 2 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:39:11 PM | 15 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:39:11 PM | 53 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:39:17 PM | 80 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:40:27 PM | 46 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:41:05 PM | 34 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:41:05 PM | 35 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:41:05 PM | 8 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:41:07 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:41:08 PM | 32 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:41:38 PM | 6 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:41:38 PM | 6 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:43:01 PM | 30 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:43:01 PM | 45 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:43:01 PM | 25 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:43:14 PM | 23 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:43:26 PM | 54 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:43:26 PM | 20 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:43:26 PM | 1 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:43:57 PM | 44 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:44:05 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:44:05 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:44:05 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:44:06 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:44:10 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:44:10 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:44:42 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:44:42 PM | 36 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:45:34 PM | 35 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:45:34 PM | 41 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:45:44 PM | 16 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:44 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:44 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:44 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:44 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:44 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:44 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:45 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:45 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 39 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 40 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 11 | 1367.00 | XCSE |
188
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 13 | 1367.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 39 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 1 | 1366.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 20 | 1366.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:45:49 PM | 10 | 1366.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 3:45:50 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:50 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:50 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:50 PM | 39 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:50 PM | 34 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:50 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:50 PM | 39 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:50 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:51 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:51 PM | 35 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:51 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:45:51 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:46:07 PM | 77 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:46:07 PM | 22 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:46:08 PM | 22 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:46:08 PM | 20 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:46:51 PM | 74 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:46:51 PM | 12 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:46:51 PM | 25 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:46:51 PM | 48 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:46:57 PM | 75 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:12 PM | 8 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:52:12 PM | 8 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:13 PM | 9 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:22 PM | 4 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:52:22 PM | 4 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:22 PM | 2 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:29 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:29 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:30 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:30 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:33 PM | 32 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:38 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:52:38 PM | 9 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:39 PM | 27 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:39 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:39 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:52:39 PM | 6 | 1368.00 | CEUX |
189
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:52:48 PM | 3 | 1368.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:52:53 PM | 24 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:53:07 PM | 31 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:53:27 PM | 1 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:55:15 PM | 13 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:15 PM | 13 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:15 PM | 1 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:15 PM | 78 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:15 PM | 42 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:15 PM | 11 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:16 PM | 18 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:16 PM | 24 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:16 PM | 6 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:16 PM | 17 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:16 PM | 42 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:16 PM | 13 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:16 PM | 82 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:28 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:28 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:28 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:55:28 PM | 5 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:55:28 PM | 13 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:55:28 PM | 14 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:55:28 PM | 5 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:55:57 PM | 26 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:55:57 PM | 36 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:56:01 PM | 67 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:56:01 PM | 11 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:56:01 PM | 3 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 3:57:31 PM | 11 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:57:31 PM | 25 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:57:31 PM | 10 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:57:31 PM | 20 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:58:16 PM | 36 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:58:25 PM | 11 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:58:26 PM | 9 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:58:47 PM | 77 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:58:47 PM | 36 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:58:47 PM | 66 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:58:48 PM | 23 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:58:48 PM | 78 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:25 PM | 10 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:26 PM | 16 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 80 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 5 | 1367.50 | CEUX |
190
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 6 | 1368.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 36 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 5 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 78 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 5 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 14 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:57 PM | 30 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:58 PM | 91 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:59:58 PM | 2 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:59:58 PM | 8 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 3:59:58 PM | 5 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:58 PM | 25 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:58 PM | 76 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:58 PM | 6 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:59 PM | 5 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:59 PM | 33 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:59 PM | 5 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:59 PM | 5 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 3:59:59 PM | 36 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:00 PM | 13 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:00 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:02 PM | 32 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:18 PM | 2 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:21 PM | 78 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:21 PM | 32 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 41 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 60 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 6 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 68 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 76 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:00:31 PM | 39 | 1367.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:00:32 PM | 44 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:32 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:32 PM | 35 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:32 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:45 PM | 4 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:45 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:45 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:45 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:45 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 11 | 1367.00 | XCSE |
191
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 11 | 1367.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 3 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 33 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 38 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 47 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 1 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:46 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:47 PM | 1 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:47 PM | 14 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:58 PM | 42 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:00:58 PM | 59 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:00 PM | 34 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:00 PM | 43 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:00 PM | 79 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:01:06 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:06 PM | 41 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:06 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:06 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:06 PM | 11 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:07 PM | 2 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:13 PM | 28 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:13 PM | 18 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:13 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:13 PM | 42 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:13 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:13 PM | 76 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:01:13 PM | 22 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:01:15 PM | 28 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:15 PM | 59 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:25 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:01:25 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:02:23 PM | 7 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:02:24 PM | 8 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:02:26 PM | 1 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:02:26 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:02:55 PM | 37 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:02:55 PM | 34 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:02:55 PM | 40 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:02:55 PM | 23 | 1365.50 | AQEU |
192
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:02:56 PM | 39 | 1365.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:02:56 PM | 42 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:02:56 PM | 24 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:03:05 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:03:28 PM | 10 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:03:46 PM | 34 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:03:46 PM | 46 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:04:42 PM | 11 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:04:52 PM | 32 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:04:52 PM | 41 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:04:52 PM | 30 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:05:00 PM | 11 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:05:11 PM | 77 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:05:25 PM | 12 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:05:43 PM | 43 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:05:43 PM | 37 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:05:43 PM | 1 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:05:43 PM | 38 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:05:43 PM | 76 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:05:43 PM | 25 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:06:37 PM | 60 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:07:25 PM | 1 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:07:25 PM | 10 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:07:26 PM | 1 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:07:30 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:07:30 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:07:30 PM | 36 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:07:30 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:07:30 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:07:30 PM | 41 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:07 PM | 14 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:07 PM | 36 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:07 PM | 78 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:07 PM | 44 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:08:16 PM | 23 | 1364.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:08:25 PM | 36 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:25 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:25 PM | 6 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:26 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:26 PM | 52 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:26 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:26 PM | 23 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:27 PM | 24 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:27 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:27 PM | 12 | 1365.00 | XCSE |
193
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:08:27 PM | 51 | 1365.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:08:27 PM | 11 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:28 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:28 PM | 27 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:30 PM | 11 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:30 PM | 11 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:33 PM | 11 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:38 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:38 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:38 PM | 12 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:48 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:48 PM | 7 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:48 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:48 PM | 19 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:08:54 PM | 42 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:54 PM | 12 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:54 PM | 42 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:08:54 PM | 1 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:09:25 PM | 3 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:09:25 PM | 2 | 1364.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:09:29 PM | 10 | 1364.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:10:02 PM | 41 | 1364.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:10:07 PM | 25 | 1364.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:10:48 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:10:48 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:10:54 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:03 PM | 2 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:11:19 PM | 36 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:11:19 PM | 6 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:11:19 PM | 6 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:11:19 PM | 9 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:11:19 PM | 34 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:11:26 PM | 10 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:11:32 PM | 32 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:11:39 PM | 42 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:39 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:39 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:39 PM | 18 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:39 PM | 15 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:40 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:40 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:40 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:40 PM | 78 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:41 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:11:41 PM | 13 | 1366.00 | XCSE |
194
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:11:57 PM | 11 | 1366.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:12:03 PM | 2 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:26 PM | 3 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 74 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 74 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 2 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 2 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 2 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 2 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 6 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 15 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 3 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:27 PM | 31 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:12:35 PM | 41 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:37 PM | 32 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 3 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 32 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 25 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 2 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 42 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 2 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 80 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 20 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 1 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 5 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 2 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 5 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 21 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 43 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 2 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 17 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 2 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 12 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 5 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 2 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 2 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 30 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 8 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 10 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 15 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 10 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 36 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 4 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 4 | 1363.50 | CEUX |
195
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 3 | 1364.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 10 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:46 PM | 46 | 1364.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:12:47 PM | 34 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:12:47 PM | 2 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:13:27 PM | 71 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:27 PM | 6 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:27 PM | 36 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:13:28 PM | 41 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:28 PM | 21 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:28 PM | 8 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:28 PM | 42 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:28 PM | 11 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:28 PM | 10 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:28 PM | 5 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:29 PM | 11 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:29 PM | 12 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:29 PM | 11 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:32 PM | 13 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:32 PM | 13 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:32 PM | 42 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:13:33 PM | 22 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:13:56 PM | 44 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:00 PM | 12 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:00 PM | 12 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:00 PM | 16 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:10 PM | 12 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:10 PM | 42 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:10 PM | 12 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:40 PM | 11 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:14:40 PM | 66 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:14:43 PM | 12 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:43 PM | 10 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:43 PM | 77 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:43 PM | 12 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:14:43 PM | 35 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:14:43 PM | 10 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:14:43 PM | 29 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 31 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 42 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 11 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 11 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 12 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 33 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 13 | 1364.00 | XCSE |
196
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 11 | 1364.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 27 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:52 PM | 13 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:53 PM | 13 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:53 PM | 30 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:53 PM | 12 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:53 PM | 13 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:53 PM | 12 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:53 PM | 42 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:54 PM | 64 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:54 PM | 15 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:55 PM | 21 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:55 PM | 42 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:55 PM | 27 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:55 PM | 13 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:55 PM | 61 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:57 PM | 11 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:14:57 PM | 27 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:15:10 PM | 80 | 1364.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:15:10 PM | 79 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:15:10 PM | 23 | 1364.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:15:59 PM | 27 | 1364.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:16:13 PM | 75 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:16:13 PM | 4 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:16:13 PM | 32 | 1364.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:16:13 PM | 12 | 1364.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:16:14 PM | 1 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:16:14 PM | 3 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:16:14 PM | 13 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:16:14 PM | 75 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:16:15 PM | 43 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:16:34 PM | 25 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:16:51 PM | 77 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:17:25 PM | 12 | 1363.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:17:57 PM | 4 | 1363.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:19:00 PM | 28 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:19:00 PM | 52 | 1363.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:19:00 PM | 36 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:19:00 PM | 7 | 1363.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:19:00 PM | 2 | 1363.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:19:27 PM | 2 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:19:27 PM | 16 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:19:50 PM | 11 | 1363.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:07 PM | 49 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:21:07 PM | 31 | 1364.50 | XCSE |
197
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:21:07 PM | 27 | 1364.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:21:07 PM | 56 | 1364.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:07 PM | 77 | 1364.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:07 PM | 45 | 1364.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:07 PM | 35 | 1364.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:21:08 PM | 14 | 1364.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:30 PM | 75 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:21:30 PM | 8 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:30 PM | 7 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:34 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:34 PM | 6 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:34 PM | 6 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:34 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:34 PM | 17 | 1364.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:43 PM | 58 | 1364.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:43 PM | 36 | 1364.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:21:44 PM | 4 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:21:44 PM | 41 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:23:07 PM | 46 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:23:32 PM | 95 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:23:32 PM | 2 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:23:32 PM | 18 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:23:32 PM | 14 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:23:32 PM | 8 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:23:32 PM | 10 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:23:57 PM | 29 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:24:00 PM | 30 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:24:00 PM | 28 | 1365.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:24:00 PM | 8 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:24:03 PM | 8 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:24:37 PM | 34 | 1364.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:24:37 PM | 8 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:25:28 PM | 8 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:26:28 PM | 1 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:28 PM | 59 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:28 PM | 6 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:28 PM | 11 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:32 PM | 53 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:32 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:32 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:32 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:32 PM | 36 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:32 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:32 PM | 6 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:33 PM | 24 | 1365.00 | CEUX |
198
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:26:33 PM | 21 | 1365.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:26:33 PM | 6 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:35 PM | 12 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:35 PM | 11 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:35 PM | 13 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:35 PM | 5 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:36 PM | 42 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:26:36 PM | 31 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:36 PM | 21 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:41 PM | 73 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:53 PM | 45 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:53 PM | 36 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:53 PM | 34 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:26:54 PM | 41 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:49 PM | 28 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:49 PM | 17 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:49 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:49 PM | 5 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:49 PM | 48 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:49 PM | 8 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:49 PM | 31 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:49 PM | 53 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:50 PM | 18 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:27:50 PM | 53 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:28:00 PM | 3 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:28:27 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:28:27 PM | 53 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:28:42 PM | 43 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:28:42 PM | 28 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:28:42 PM | 36 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:28:42 PM | 54 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:28:44 PM | 11 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:03 PM | 13 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:17 PM | 35 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:17 PM | 6 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:17 PM | 36 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:17 PM | 5 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:17 PM | 25 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 11 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 18 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 30 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 30 | 1365.50 | XCSE |
199
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 11 | 1365.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 30 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 21 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 36 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 17 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 26 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:26 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:29:27 PM | 12 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:27 PM | 9 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:29:27 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:30:17 PM | 11 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:30:25 PM | 2 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:30:43 PM | 10 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:30:49 PM | 3 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:31:04 PM | 12 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:31:05 PM | 42 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:31:31 PM | 20 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:31:31 PM | 30 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:31:37 PM | 36 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:31:46 PM | 62 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:31:55 PM | 31 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:00 PM | 11 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:00 PM | 10 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:03 PM | 15 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:03 PM | 11 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:11 PM | 58 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:12 PM | 34 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:15 PM | 28 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:16 PM | 8 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:32:16 PM | 17 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:16 PM | 56 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:32:17 PM | 2 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:32:28 PM | 63 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:32:28 PM | 10 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:32:28 PM | 22 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:32:28 PM | 15 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:32:28 PM | 16 | 1366.00 | AQEU |
200
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:32:45 PM | 51 | 1366.00 | CEUX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:32:46 PM | 7 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:32:46 PM | 64 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:32:46 PM | 22 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:32:47 PM | 23 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:32:48 PM | 5 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:33:07 PM | 48 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:26 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:26 PM | 25 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:26 PM | 2 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:26 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:26 PM | 53 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:26 PM | 75 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:33:26 PM | 24 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:33:27 PM | 9 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:27 PM | 42 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:27 PM | 50 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:28 PM | 73 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:31 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:31 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:31 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:31 PM | 53 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:38 PM | 5 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:39 PM | 18 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:39 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:39 PM | 53 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:39 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:40 PM | 43 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:53 PM | 53 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:53 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:53 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:54 PM | 10 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:33:59 PM | 16 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:00 PM | 40 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:00 PM | 22 | 1366.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:34:37 PM | 5 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:34:37 PM | 42 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:34:37 PM | 36 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:34:37 PM | 13 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:34:41 PM | 30 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:41 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:41 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:41 PM | 1 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:34:45 PM | 7 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:45 PM | 10 | 1367.00 | XCSE |
201
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:34:45 PM | 13 | 1367.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:34:45 PM | 11 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:45 PM | 30 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:45 PM | 53 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:51 PM | 12 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:34:51 PM | 13 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:01 PM | 1 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:01 PM | 2 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:01 PM | 25 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:01 PM | 1 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:01 PM | 32 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:01 PM | 28 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:01 PM | 22 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:01 PM | 3 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 3 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 2 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 3 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 7 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 15 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 2 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 1 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 3 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 3 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 10 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 2 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 3 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:03 PM | 3 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:08 PM | 79 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:08 PM | 5 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:08 PM | 53 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:08 PM | 15 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:08 PM | 7 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:08 PM | 11 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:08 PM | 10 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:08 PM | 28 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 76 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 21 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 10 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 45 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 25 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 3 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 7 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 4 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 4 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 2 | 1368.50 | TQEX |
202
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 2 | 1368.50 | TQEX |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:35:20 PM | 22 | 1369.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:35:25 PM | 10 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:25 PM | 12 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:25 PM | 11 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:26 PM | 5 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:34 PM | 25 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:34 PM | 7 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:34 PM | 14 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 18 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 9 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 36 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 20 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 6 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 48 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 5 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 5 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 3 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 3 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 2 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 6 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 17 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:35:37 PM | 5 | 1367.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:36:18 PM | 65 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:18 PM | 36 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:27 PM | 15 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:36:30 PM | 12 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:30 PM | 22 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:30 PM | 1 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:30 PM | 13 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:30 PM | 53 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:30 PM | 12 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:36:31 PM | 12 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:31 PM | 10 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:31 PM | 53 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:31 PM | 2 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:31 PM | 24 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:31 PM | 23 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:36:42 PM | 7 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:57 PM | 10 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:36:57 PM | 11 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:36:57 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:36:57 PM | 3 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:36:57 PM | 8 | 1368.00 | CEUX |
203
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:36:59 PM | 69 | 1367.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:37:08 PM | 6 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:37:08 PM | 15 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:37:08 PM | 6 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:37:08 PM | 12 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:37:26 PM | 7 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:37:26 PM | 22 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:37:37 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:37:37 PM | 6 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:37:37 PM | 6 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:37:37 PM | 25 | 1367.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:37:46 PM | 10 | 1367.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:37:46 PM | 63 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:38:34 PM | 26 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:38:34 PM | 30 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:38:34 PM | 15 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:38:47 PM | 65 | 1367.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:39:14 PM | 22 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:39:14 PM | 75 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:39:14 PM | 8 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:39:16 PM | 83 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:39:17 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:39:37 PM | 11 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:39:48 PM | 52 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:40:32 PM | 1 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:32 PM | 1 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:32 PM | 5 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:33 PM | 90 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:40:33 PM | 9 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:40:40 PM | 53 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:40 PM | 11 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:40 PM | 3 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:45 PM | 39 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:40:48 PM | 53 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:48 PM | 10 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:48 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:48 PM | 79 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:48 PM | 12 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:40:48 PM | 27 | 1367.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 32 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 42 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 2 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 25 | 1368.00 | XCSE |
204
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 46 | 1368.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 10 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:00 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:01 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:01 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:01 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:01 PM | 93 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:03 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:03 PM | 53 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:03 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:03 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:04 PM | 12 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:04 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:04 PM | 11 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:15 PM | 5 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:17 PM | 56 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:41:37 PM | 53 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:37 PM | 12 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:37 PM | 11 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:39 PM | 93 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:40 PM | 53 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:40 PM | 13 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:41:40 PM | 11 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:05 PM | 12 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:05 PM | 11 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:05 PM | 53 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:06 PM | 39 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:15 PM | 46 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:42:18 PM | 35 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:18 PM | 19 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:18 PM | 17 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:18 PM | 42 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:18 PM | 9 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:42:18 PM | 42 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:42:18 PM | 25 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:42:23 PM | 13 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:23 PM | 9 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:42:23 PM | 12 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:43:02 PM | 52 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:43:02 PM | 11 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:43:02 PM | 101 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:43:18 PM | 49 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:43:27 PM | 26 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:43:36 PM | 28 | 1369.00 | XCSE |
205
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:43:36 PM | 53 | 1369.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:43:38 PM | 37 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:43:38 PM | 8 | 1369.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:43:46 PM | 40 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:43:46 PM | 29 | 1369.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:43:49 PM | 22 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:44:02 PM | 28 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:44:02 PM | 19 | 1369.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:44:08 PM | 13 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:44:08 PM | 12 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:44:08 PM | 53 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:44:08 PM | 50 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:44:08 PM | 20 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:44:08 PM | 22 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:44:13 PM | 12 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:44:23 PM | 7 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:44:28 PM | 10 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:44:28 PM | 28 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:44:28 PM | 10 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:44:28 PM | 22 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:45:00 PM | 12 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:45:08 PM | 24 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:45:08 PM | 42 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:45:28 PM | 1 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:45:28 PM | 4 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:45:28 PM | 31 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:45:28 PM | 2 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:46:15 PM | 41 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:46:17 PM | 33 | 1368.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:46:22 PM | 11 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:22 PM | 5 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:22 PM | 1 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:22 PM | 5 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:22 PM | 42 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:46:24 PM | 13 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:24 PM | 1 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:24 PM | 11 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:24 PM | 44 | 1368.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:46:29 PM | 30 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:29 PM | 13 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:29 PM | 53 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:29 PM | 13 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:29 PM | 12 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:29 PM | 8 | 1368.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:46:29 PM | 5 | 1368.50 | XCSE |
206
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:46:29 PM | 12 | 1368.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:46:47 PM | 21 | 1368.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:47:24 PM | 1 | 1368.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:47:25 PM | 30 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:47:25 PM | 21 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:47:26 PM | 11 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:47:37 PM | 22 | 1368.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:47:55 PM | 47 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:47:55 PM | 34 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:47:55 PM | 11 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:02 PM | 47 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:48:02 PM | 12 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:04 PM | 5 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:04 PM | 42 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:04 PM | 5 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:05 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:48:05 PM | 13 | 1368.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:48:05 PM | 36 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:05 PM | 2 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:05 PM | 2 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:05 PM | 11 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:07 PM | 33 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:48:07 PM | 37 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:07 PM | 25 | 1367.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:07 PM | 2 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:07 PM | 11 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:07 PM | 3 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:07 PM | 6 | 1368.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:48:25 PM | 33 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:36 PM | 41 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:36 PM | 8 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:52 PM | 14 | 1367.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:48:52 PM | 5 | 1367.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:48:55 PM | 12 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:48:55 PM | 34 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:49:19 PM | 27 | 1368.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:49:26 PM | 78 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:49:26 PM | 17 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:49:26 PM | 51 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:49:26 PM | 5 | 1368.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:49:26 PM | 18 | 1367.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:49:26 PM | 23 | 1367.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:49:27 PM | 13 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:49:27 PM | 11 | 1367.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:49:45 PM | 8 | 1367.00 | AQEU |
207
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:50:00 PM | 11 | 1367.00 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:50:00 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:50:00 PM | 8 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:50:14 PM | 25 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:50:14 PM | 5 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:50:19 PM | 6 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:50:19 PM | 4 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:50:24 PM | 5 | 1366.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:50:47 PM | 1 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:50:52 PM | 1 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:50:57 PM | 10 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:50:57 PM | 5 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:50:57 PM | 16 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:50:57 PM | 1 | 1366.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:51:07 PM | 42 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:07 PM | 33 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:07 PM | 24 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:07 PM | 11 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:51:08 PM | 2 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:08 PM | 33 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:09 PM | 101 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:51:09 PM | 51 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:10 PM | 12 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:10 PM | 35 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:51:11 PM | 13 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:51:11 PM | 26 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:11 PM | 30 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:12 PM | 1 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:51:27 PM | 45 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:27 PM | 22 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:51:32 PM | 12 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:32 PM | 21 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:51:47 PM | 70 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:52:07 PM | 4 | 1365.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:52:10 PM | 12 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:52:10 PM | 35 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:52:10 PM | 13 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:52:10 PM | 10 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:52:10 PM | 31 | 1366.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:52:34 PM | 100 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:52:34 PM | 11 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:52:34 PM | 9 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:52:55 PM | 5 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:52:57 PM | 8 | 1365.00 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:52:57 PM | 6 | 1365.50 | CEUX |
208
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:52:58 PM | 53 | 1365.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:52:58 PM | 18 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:52:59 PM | 5 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:52:59 PM | 5 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:02 PM | 11 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:19 PM | 10 | 1365.00 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:53:26 PM | 36 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 13 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 3 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 85 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 5 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 6 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 42 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 2 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 3 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 3 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 12 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:27 PM | 2 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:28 PM | 12 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:28 PM | 62 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:28 PM | 5 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:28 PM | 22 | 1365.50 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:29 PM | 6 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:53:38 PM | 8 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:41 PM | 42 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:41 PM | 42 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:41 PM | 6 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:41 PM | 6 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:41 PM | 5 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:51 PM | 42 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:51 PM | 6 | 1366.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:53:55 PM | 101 | 1366.00 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:53:55 PM | 33 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:53:55 PM | 30 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:55 PM | 7 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:55 PM | 4 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:53:55 PM | 5 | 1366.00 | TQEX |
| GENMAB A/S | 28-Mar-25 | 4:54:02 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:02 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:03 PM | 26 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:03 PM | 64 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:03 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:04 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:04 PM | 12 | 1366.50 | XCSE |
209
Exhibit 99.1(a)
APPENDIX Share buy-back programme - Specification for March 26 – March 28, 2025

| GENMAB A/S | 28-Mar-25 | 4:54:04 PM | 30 | 1366.50 | XCSE |
|---|---|---|---|---|---|
| GENMAB A/S | 28-Mar-25 | 4:54:04 PM | 6 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:04 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:04 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:05 PM | 55 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:07 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:07 PM | 53 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:07 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:14 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:14 PM | 53 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:14 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:15 PM | 100 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:15 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:15 PM | 13 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:15 PM | 53 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:19 PM | 100 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:33 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:40 PM | 1 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:40 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:40 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:40 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:40 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:40 PM | 12 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:40 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:41 PM | 11 | 1366.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:45 PM | 25 | 1365.50 | CEUX |
| GENMAB A/S | 28-Mar-25 | 4:54:51 PM | 20 | 1365.50 | AQEU |
| GENMAB A/S | 28-Mar-25 | 4:54:56 PM | 23 | 1365.50 | XCSE |
| GENMAB A/S | 28-Mar-25 | 4:54:58 PM | 21 | 1365.50 | XCSE |
210