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
December 17, 2025
(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: December 17, 2025
EXHIBIT INDEX
| Exhibit | Description |
|---|---|
| 99 | 6K on 12/17/2025 |
EX-99
www.umc.com
Exhibit
Exhibit Description
99.1 Announcement on 2025/12/17: The board meeting approved capital budget execution
99.2 Announcement on 2025/12/17: To announce related materials on participating in the capital increase of Unimicron Technology Corp.
Exhibit 99.1
The board meeting approved capital budget execution
Date of the resolution of the board of directors or shareholders meeting: 2025/12/17
Content of the investment plan: capital budget execution
Projected monetary amount of the investment: NT$ 30,096 million
Projected date of the investment: by capital budget plan
Source of capital funds: working capital
Specific purpose: capacity deployment
Any other matters that need to be specified: none
Exhibit 99.2
To announce related materials on participating in the capital increase of Unimicron Technology Corp.
Name of the securities: Unimicron Technology Corp. common shares
Trading date: 2025/12/17
Date of the board of directors’ resolution: 2025/12/17
Other approval date: NA
Amount, unit price, and total monetary amount of the transaction:
Trading volume: Not exceeding 6,034,482 shares;
Unit price: NTD 116;
Total amount: Not exceeding NTD 700,000,000
Gain (or loss) through disposal (not applicable in case of acquisition of securities): NA
Relationship with the underlying company of the trade:
Unimicron Technology Corp.; the Company’s associate
- Current cumulative amount held, monetary amount, and shareholding percentage of cumulative holdings of the securities being traded (including the current trade), and status of any restriction of rights (e.g. pledges):
Cumulative volume: 204,912,528 shares;
Monetary amount: NTD 14,292,544,874;
Percentage of holdings: 13.01%;
Status of any restriction of rights: None
- Current ratio of securities investment (including the current trade, as listed in article 3 of Regulations Governing the Acquisition and Disposal of Assets by Public Companies) to the total assets and equity attributable to owners of the parent as shown in the most recent financial statement and working capital as shown in the most recent financial statement as of the present:
Ratio of total assets:35.09%;
Ratio of shareholder's equity:52.17%;
Working capital as shown in the most recent financial statement: NTD 54,856,890,000
Concrete purpose of the acquisition or disposal: strategic investment
Any dissenting opinions of directors to the present transaction: NA
Whether the counterparty of the current transaction is a related party: Yes
Trading counterparty and its relationship with the Company:
Unimicron Technology Corp.; the Company’s associate
Date of ratification by supervisors or approval by the audit committee: 2025/12/17
Date on which material information regarding the same event has been previously released: NA
Any other matters that need to be specified:
The Company will subscribe the new shares issued by Unimicron Technology Corp. for its cash capital increase based on shareholding ratio. Further, if the employees and other shareholders waive the subscription rights and Unimicron Technology Corp. inquiries the specific person, the Company will subscribe the remaining part of issued shares not exceeding NTD 179,661,468.