United Microelectronics Corp SEC filings UMC
United Microelectronics Corp has 742 filings in SEC EDGAR's recent list, going back to Feb 14, 1997. Its latest annual report, Form 20-F, was filed on Apr 30, 2026 for the period ended Dec 31, 2025. The most recent current report (Form 6-K) was filed on Nov 3, 2026. The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| 4 | Insider transaction | Sep 22, 2026 | Sep 22, 2026 |
| 3 | Initial insider ownership | Sep 18, 2026 | Sep 11, 2026 |
| 4 | Insider transaction | Sep 17, 2026 | Sep 16, 2026 |
| 4 | Insider transaction | Sep 8, 2026 | Sep 7, 2026 |
| 4 | Insider transaction | Jul 13, 2026 | Jul 13, 2026 |
| 4 | Insider transaction | Jun 30, 2026 | Jun 30, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | May 1, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | May 1, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| 3 | Initial insider ownership | May 7, 2026 | Apr 29, 2026 |
| SCHEDULE 13G/A | Amended ownership over 5% (passive) | Apr 29, 2026 | — |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| 3 | Initial insider ownership | Mar 18, 2026 | Mar 18, 2026 |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 5, 2024 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 10, 2023 | — |
| SC 13G | Ownership over 5% (passive) | Feb 8, 2022 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Jun 9, 2020 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Jun 9, 2020 | — |
| SC 13G | Ownership over 5% (passive) | Feb 13, 2020 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 6, 2020 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 13, 2019 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 7, 2019 | — |
| SC 13G | Ownership over 5% (passive) | Feb 13, 2018 | — |
| SC 13G | Ownership over 5% (passive) | Feb 1, 2018 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 10, 2011 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 9, 2011 | — |
| SC 13G | Ownership over 5% (passive) | Jan 29, 2010 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 12, 2004 | — |
| SC 13G | Ownership over 5% (passive) | Mar 24, 2003 | — |
| SC 13G | Ownership over 5% (passive) | Feb 13, 2003 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Feb 13, 2002 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Jul 10, 2001 | — |
| SC 13G | Ownership over 5% (passive) | May 22, 2001 | — |
| SC 13G/A | Amended ownership over 5% (passive) | May 8, 2001 | — |
| SC 13G/A | Amended ownership over 5% (passive) | Mar 5, 2001 | — |
| SC 13G | Ownership over 5% (passive) | Feb 12, 2001 | — |
| SC 13G | Ownership over 5% (passive) | Feb 9, 2001 | — |
| SC 13D/A | Amended ownership over 5% (active) | May 11, 2000 | — |
| SC 13D/A | Amended ownership over 5% (active) | Nov 22, 1999 | — |
| SC 13D/A | Amended ownership over 5% (active) | Feb 26, 1997 | — |
| SC 13D | Ownership over 5% (active) | Feb 21, 1997 | — |
| SC 13D | Ownership over 5% (active) | Feb 14, 1997 | — |
Showing 65 filings. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
New to this? Read What Are SEC Filings? 10-K, 10-Q, 8-K and Other Forms Explained.
Company profile
- Industry
- Semiconductors & Related Devices (SIC 3674)
- Listed as
- UMC (NYSE)
- Fiscal year ends
- December 31
- Incorporated in
- Taiwan
- Headquarters
- Taipei, Taiwan
- SEC filer status
- Large accelerated filer
- SEC CIK
- 1033767
Other Semiconductors & Related Devices companies
- Nvidia Corp NVDA
- Broadcom Inc. AVGO
- Micron Technology Inc MU
- Advanced Micro Devices Inc AMD
- Intel Corp INTC
- Applied Materials Inc /DE AMAT
- Texas Instruments Inc TXN
- Arm Holdings PLC /UK ARM
Source: SEC EDGAR filings. This is company-reported data, not investment advice.