6-K
United Microelectronics Corp (UMC)
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 6-K
REPORT OF FOREIGN ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16
OF THE SECURITIES EXCHANGE ACT OF 1934
January 7, 2026
(Commission File Number: 001-15128)
United Microelectronics Corporation
(Translation of registrant’s name into English)
No. 3 Li-Hsin 2nd Road,
Hsinchu Science Park,
Hsinchu, Taiwan, R.O.C.
(Address of principal executive office)
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
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101 (b) (1):
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101 (b) (7):
SIGNATURES
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, thereto duly authorized.
| United Microelectronics Corporation | |
|---|---|
| By: | Chitung Liu |
| Name: | Chitung Liu |
| Title: | CFO |
Date: January 7, 2026
EXHIBIT INDEX
| Exhibit | Description |
|---|---|
| 99.1 | 6K on 01/07/2026 |
EX-99.1
www.umc.com
Exhibit
Exhibit Description
99.1 Announcement on 2026/01/07: December Revenue
Exhibit 99.1
United Microelectronics Corporation
January 7, 2026
This is to report the changes or status of 1) Sales volume, 2) Funds lent to other parties, 3) Endorsements and guarantees, and 4) Financial derivative transactions for the period of December 2025.
- Sales volume (NT$ Thousand)
| Period | Items | 2025 | 2024 | Changes | % |
|---|---|---|---|---|---|
| December | Net sales | 19,280,724 | 18,965,818 | 314,906 | 1.66% |
| Year-to-Date | Net sales | 237,553,199 | 232,302,584 | 5,250,615 | 2.26% |
Funds lent to other parties (NT$ Thousand): None
Endorsements and guarantees (NT$ Thousand)
| Balance as of period end | This Month<br>(actual amount provided) | Last Month<br>(actual amount provided) | Limit of lending |
|---|---|---|---|
| UMC | 0 | 0 | 162,477,099 |
| Note: Since USC(Xiamen)’s syndicated loan from banks has been prepaid early, the Company’s endorsement to USC(Xiamen)’s syndicated loan from banks is released. |
- Financial derivatives transactions:
a Not under hedging accounting: NT$ thousand
UMC
| Financial instruments | Option | Forwards | IRS | ||
|---|---|---|---|---|---|
| Put | Call | ||||
| Deposit Paid | 0 | 0 | 0 | 0 | |
| Royalty Income (Paid) | 0 | 0 | 0 | 0 | |
| Unwritten-off Trading | |||||
| Contracts | 0 | 0 | 689,700 | 0 | |
| Fair Value | 0 | 0 | (653) | 0 | |
| Net profit (loss) from Fair Value | 0 | 0 | 384 | 0 | |
| Written-off Trading | |||||
| Contracts | 0 | 0 | 5,277,195 | 0 | |
| Realized profit (loss) | 0 | 0 | (547) | 0 |