# EDGAR Filing Document

**Accession Number:** 0001033767
**File Stem:** 0001193125-25-307415
**Filing Date:** 2025-12
**Character Count:** 10935
**Document Hash:** 5a23db3982eab6eb8ca79b483d1dda22
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-307415.hdr.sgml**: 20251204

**ACCESSION NUMBER**: 0001193125-25-307415

**CONFORMED SUBMISSION TYPE**: 6-K

**PUBLIC DOCUMENT COUNT**: 3

**CONFORMED PERIOD OF REPORT**: 20251204

**FILED AS OF DATE**: 20251204

**DATE AS OF CHANGE**: 20251204

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** UNITED MICROELECTRONICS CORP
- **CENTRAL INDEX KEY:** 0001033767
- **STANDARD INDUSTRIAL CLASSIFICATION:** SEMICONDUCTORS & RELATED DEVICES [3674]
- **ORGANIZATION NAME:** 04 Manufacturing
- **EIN:** 000000000
- **STATE OF INCORPORATION:** F5
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 6-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-15128
- **FILM NUMBER:** 251548208

**BUSINESS ADDRESS:**
- **STREET 1:** 8F, NO.68, SEC. 1, NEIHU RD.,
- **CITY:** TAIPEI
- **STATE:** F5
- **ZIP:** 11493
- **BUSINESS PHONE:** 886-2-2658-9168

**MAIL ADDRESS:**
- **STREET 1:** 8F, NO.68, SEC. 1, NEIHU RD.,
- **CITY:** TAIPEI
- **STATE:** F5
- **ZIP:** 11493

**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

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**FORM 6-K** 

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**REPORT OF FOREIGN ISSUER** 

**PURSUANT TO RULE 13a-16 OR 15d-16** 

**OF THE SECURITIES EXCHANGE ACT OF 1934** 

**December 4, 2025** 

**(Commission File Number: 001-15128)** 

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**United Microelectronics Corporation**

**(Translation of registrant's name into English)** 

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**No. 3 Li-Hsin 2nd Road, Hsinchu Science Park, Hsinchu, Taiwan, R.O.C.** 

**(Address of principal executive office)** 

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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): 

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**<u>SIGNATURES</u>** 

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.

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| | |
|:---|:---|
| United Microelectronics Corporation | United Microelectronics Corporation |
| By: | Chitung Liu |
| Name: | Chitung Liu |
| Title: | CFO |

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Date: December 4, 2025

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**EXHIBIT INDEX** 

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| | |
|:---|:---|
| **Exhibit**  | **Description**  |
| <br>99 | <br>[<u>6K on 12/04/2025</u>](umc-ex99.htm) |

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## Ex-99

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

![img239034952_0.jpg](img239034952_0.jpg)**www.umc.com**

**Exhibit**

<u>Exhibit</u> <u>Description</u> 

99.1 Announcement on 2025/12/04: UMC and Polar Collaborate to Meet Growing Demand for U.S. Onshore Semiconductor Manufacturing

99.2 Announcement on 2025/12/04: November Revenue

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**Exhibit 99.1**

**UMC and Polar Collaborate to Meet Growing Demand for U.S. Onshore Semiconductor Manufacturing**

1. Date of occurrence of the event: 2025/12/04

2. Counterparty to the contract or commitment: Polar Semiconductor, LLC ("Polar")

3. Relationship with the Company: No

4. Starting and ending dates (or rescission date) of the contract or commitment:

Both parties signed the MOU on 2025/12/04

5. Major content (not applicable where rescinded):

UMC and Polar have signed a MOU to explore collaboration on delivering scalable U.S.-based 8-inch production of high-quality wafers

6. Restrictive covenants (not applicable where rescinded): No

7. Commitment (not applicable where rescinded): No

8. Any other important agreement (not applicable where rescinded): No

9. Effect on company finances and business:

This MOU confirms the consensus of collaboration between the two parties and there has been no significant impact on the Company's finances and business.

If both parties sign a formal agreement, the details and terms of the collaboration shall be based on the material information officially announced by our company.

10. Concrete purpose/objective:

Enhance the company's resilience to changes in the global political and economic environment in order to address our customers' needs for more made-in-USA chips.

11. Any other matters that need to be specified (the information disclosure also meets the requirements of Article 7, subparagraph 8 of the Securities and Exchange Act Enforcement Rules, which brings forth a significant impact on shareholders rights or the price of the securities on public companies.):

UMC and Polar Collaborate to Meet Growing Demand for U.S. Onshore Semiconductor Manufacturing

HSINCHU, Taiwan, and BLOOMINGTON, Minn., December 4, 2025 – United Microelectronics Corporation (NYSE: UMC: TWSE: 2303) ("UMC"), a leading global semiconductor foundry, and Polar Semiconductor, LLC ("Polar"), a U.S.-owned and operated foundry specializing in high-voltage, power, and sensor technologies, today announced they have signed a Memorandum of Understanding (MOU) to explore collaboration on delivering scalable U.S.-based 8-inch production of high-quality wafers that are essential across pillar industries including automotive, data centers, consumer electronics, and aerospace & defense.

Under the MOU, Polar and UMC will identify devices for Polar to manufacture at its recently expanded 8-inch facility in Minnesota. By combining Polar's proven manufacturing capabilities with UMC's comprehensive 8-inch technology portfolio and global customer base, this partnership is set to drive growth for both companies while supporting customers' multi-sourcing strategies. In addition, the collaboration will strengthen 8-inch wafer manufacturing in the U.S., contributing to supply chain resilience amid shifting geopolitical dynamics and ensuring a secure domestic supply of power semiconductors critical to automotive, electric grids, robotic manufacturing, data centers, and more.

Ken Obuszewski, Vice President of Marketing of Polar, said, "This partnership is aligned with Polar's strategy to meet the growing demand for domestic manufacturing, including the need to onshore semiconductor solutions from U.S. and global customers. With deep foundry customer relationships and a robust portfolio of specialized technologies, partnership with UMC is proof of

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Polar's capability to be a value-added silicon foundry in specialized technologies focused on power and sensors."

Oliver Chang, Senior Vice President of Global Sales of UMC, said, "UMC is committed to enabling our customers' success through a broad range of foundry technologies and geographically diverse manufacturing options. We are excited to collaborate with Polar to explore new applications and markets. This partnership directly addresses our customers' needs for more made-in-USA chips, reflecting UMC's dedication to delivering value through innovative solutions and mutually beneficial partnerships."

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**Exhibit 99.2**

**United Microelectronics Corporation**

December 4, 2025

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 November 2025.

1)Sales volume (NT$ Thousand)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Period | Items | 2025 | 2024 | Changes | % |
| November | Net sales | 21233847 | 20049182 | 1184665 | 5.91% |
| Year-to-Date | Net sales | 218272475 | 213336766 | 4935709 | 2.31% |

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

3)Endorsements and guarantees (NT$ Thousand)

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| | | | |
|:---|:---|:---|:---|
| Balance as of period end | This Month(actual amount provided) | Last Month(actual amount provided) | Limit of lending |
| *UMC* | 0 | 0 | 162477099 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*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.* | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*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.* | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*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.* | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*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.* |

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4)Financial derivatives transactions:

a Not under hedging accounting: NT$ thousand

***UMC***

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| | | | | |
|:---|:---|:---|:---|:---|
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Financial instruments* | &nbsp;&nbsp;Option | &nbsp;&nbsp;Option | &nbsp;&nbsp;Forwards | &nbsp;&nbsp;IRS |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Financial instruments* | &nbsp;&nbsp;Put | &nbsp;&nbsp;Call | &nbsp;&nbsp;Forwards | &nbsp;&nbsp;IRS |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Deposit Paid* | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Royalty Income (Paid)* | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Unwritten-off Trading* |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Contracts* | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;188040 | &nbsp;&nbsp;0 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Fair Value* | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;(1836) | &nbsp;&nbsp;0 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Net profit (loss) from Fair Value* | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;(799) | &nbsp;&nbsp;0 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Written-off Trading* |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Contracts* | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;5090615 | &nbsp;&nbsp;0 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*Realized profit (loss)* | &nbsp;&nbsp;0 | &nbsp;&nbsp;0 | &nbsp;&nbsp;787 | &nbsp;&nbsp;0 |

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