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

 

 

2


 

 

EXHIBIT INDEX

Exhibit

 

Description

 

99.1

 

 

6K on 01/07/2026

 

3


 

img208044986_0.jpg 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.

 

1)
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%

 

2)
Funds lent to other parties (NT$ Thousand): None

 

3)
Endorsements and guarantees (NT$ Thousand)

Balance as of period end

This Month

(actual amount provided)

Last Month

(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.

4)
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