GBDC · GOLUB CAPITAL BDC, Inc.

Due to his control of GEMS Fund 4, L.P., Mr. Golub may be viewed as having investment power over all of the shares owned by such entity although voting rights were passed through to the limited partners.Mr. Golub disclaims beneficial ownership of such shares of GBDC common stock held by GEMS Fund 4, L.P., except to the extent of his pecuniary interest therein.

Due to his control of GEMS Fund 4, L.P., Mr. Golub may be viewed as having investment power over all of the shares owed by such entity although voting rights have been passed through to the limited partners. Mr. Golub disclaims beneficial ownership of such shares of common stock held by GEMS Fund 4, L.P. except to the extent of his pecuniary interest therein.

Due to his control and ownership in GC Advisors LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity. Mr. Golub disclaims beneficial ownership of such shares of common stock held by GC Advisors LLC except to the extent of his pecuniary interest therein.

Due to his control and ownership in Golub Onshore GP, LLC, Mr. Golub is viewed as having investment power over all of the shares owned by such entity.

Due to his control and ownership in GC Advisors LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity. Mr. Golub disclaims beneficial ownership of such shares of common stock held by GC Advisors LLC except to the extent of his pecuniary interest therein.

Due to his control and ownership in GGP Holdings, L.P., Mr. Golub is viewed as having investment power over all the shares owned by such entity. Due to his control and ownership in GC Advisors LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity. Mr. Golub disclaims beneficial ownership of such shares of common stock held by each of GGP Holdings, L.P. and GC Advisors LLC except to the extent of his pecuniary interest therein.

Due to his control and ownership of GGP Class B-P, LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Due to his control and ownership in GGP Holdings, L.P., Mr. Golub is viewed as having investment power over all the shares owned by such entity. Due to his control and ownership in GC Advisors LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity. Mr. Golub disclaims beneficial ownership of such shares of common stock held by each of GGP Holdings, L.P. and GC Advisors LLC except to the extent of his pecuniary interest therein.

Due to his control and ownership in Golub Onshore GP, LLC, Mr. Golub is viewed as having investment power over all of the shares owned by such entity.

Due to his control and ownership of GGP Class B-P, LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Due to his control of and ownership interest in GCOP, LLC, Mr. Golub may be viewed as having investment power over all of the shares owned by such entity.

Due to his control of and ownership interest in GCOP LLC, Mr. Golub is viewed as having investment power over all of the shares owned by such entity.

On December 20, 2024, Mr. Webster donated 7,100 shares of GBDC common stock to The Nature Conservancy.

Reflects involuntary disposition of a fractional share effected by broker upon consolidation of brokerage accounts.

Reflects the weighted average price of purchases on September 6, 2024. The shares were purchased in multiple transactions at prices ranging from $14.70 to $14.97, inclusive.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on September 6, 2024. The shares were purchased in multiple transactions at prices ranging from $14.70 to $14.97, inclusive.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on September 5, 2024. The shares were purchased in multiple transactions at prices ranging from $14.86 to $14.96, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on September 5, 2024. The shares were purchased in multiple transactions at prices ranging from $14.86 to $14.96, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on September 4, 2024. The shares were purchased in multiple transactions at prices ranging from $14.87 to $15.04, inclusive.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on September 4, 2024. The shares were purchased in multiple transactions at prices ranging from $14.87 to $15.04, inclusive.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on September 3, 2024. The shares were purchased in multiple transactions at prices ranging from $14.84 to $14.96, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on September 3, 2024. The shares were purchased in multiple transactions at prices ranging from $14.84 to $14.96, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 30, 2024. The shares were purchased in multiple transactions at prices ranging from $14.74 to $14.93, inclusive.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 30, 2024. The shares were purchased in multiple transactions at prices ranging from $14.74 to $14.93, inclusive.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 29, 2024. The shares were purchased in multiple transactions at prices ranging from $15.00 to $15.21, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 29, 2024. The shares were purchased in multiple transactions at prices ranging from $15.00 to $15.21, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 28, 2024. The shares were purchased in multiple transactions at prices ranging from $15.00 to $15.11, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnote (1) to this Form 4.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 28, 2024. The shares were purchased in multiple transactions at prices ranging from $15.00 to $15.11, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnote (1) to this Form 4.

Due to his control and ownership of GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 27, 2024. The shares were purchased in multiple transactions at prices ranging from $14.98 to $15.13, inclusive.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 27, 2024. The shares were purchased in multiple transactions at prices ranging from $14.98 to $15.13, inclusive.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 26, 2024. The shares were purchased in multiple transactions at prices ranging from $14.94 to $15.07, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 26, 2024. The shares were purchased in multiple transactions at prices ranging from $14.94 to $15.07, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 23, 2024. The shares were purchased in multiple transactions at prices ranging from $14.99 to $15.10, inclusive.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 23, 2024. The shares were purchased in multiple transactions at prices ranging from $14.99 to $15.10, inclusive.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 22, 2024. The shares were purchased in multiple transactions at prices ranging from $14.99 to $15.10, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 22, 2024. The shares were purchased in multiple transactions at prices ranging from $14.99 to $15.10, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 21, 2024. The shares were purchased in multiple transactions at prices ranging from $14.85 to $15.02, inclusive.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 21, 2024. The shares were purchased in multiple transactions at prices ranging from $14.85 to $15.02, inclusive.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 20, 2024. The shares were purchased in multiple transactions at prices ranging from $14.75 to $14.84, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 20, 2024. The shares were purchased in multiple transactions at prices ranging from $14.75 to $14.84, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership in GGP Class B-P LLC, Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 19, 2024. The shares were purchased in multiple transactions at prices ranging from $14.65 to $14.78, inclusive.

Due to his control and ownership in GGP Class B-P., Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 19, 2024. The shares were purchased in multiple transactions at prices ranging from $14.65 to $14.78, inclusive.

Due to his control and ownership in GGP Class B-P., Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 16, 2024. The shares were purchased in multiple transactions at prices ranging from $14.65 to $14.72, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership in GGP Class B-P., Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Reflects the weighted average price of purchases on August 16, 2024. The shares were purchased in multiple transactions at prices ranging from $14.65 to $14.72, inclusive. Mr. Golub undertakes to provide to Golub Capital BDC, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (1) and (3) to this Form 4.

Due to his control and ownership in GGP Class B-P., Mr. Golub is viewed as having investment power over all the shares owned by such entity.

On August 12, 2024, the reporting person filed a Form 4 that inadvertently omitted the full number of shares purchased due to administrative oversight. This amendment is being filed to correct the number of shares purchased from 3,000 to 3,500 in transactions that occurred on August 9, 2024 by certain trusts for which the reporting person serves as trustee.

Includes shares held in trusts for the benefit of Ms. Rival's children, for which Ms. Rival serves as trustee.

Due to his control and ownership in GGP Class B-P., Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Due to his control and ownership in GGP Class B-P., Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Due to his control and ownership in GGP Class B-P., Mr. Golub is viewed as having investment power over all the shares owned by such entity.

Due to his control and ownership in GGP Class B-P., Mr. Golub is viewed as having investment power over all the shares owned by such entity.