Welcome to our dedicated page for United Microelec SEC filings (Ticker: UMC), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
United Microelectronics Corporation filings document the company’s reporting as a foreign issuer with U.S.-listed securities, including Form 20-F annual reporting and Form 6-K current reports. The filings cover consolidated financial statements, monthly sales volume, quarterly operating results, accounting differences between TIFRSs and IFRS Accounting Standards issued by the IASB, and disclosures on funds lent, endorsements and guarantees, and derivative transactions.
UMC’s regulatory documents also record board and governance actions, capital budget execution, share repurchase programs, cancellation of restricted employee share awards, and trading or pledging of common shares by directors, executive officers, and 10% shareholders. These filings tie the company’s semiconductor foundry business to formal disclosures on capital structure, financial reporting, ownership activity, and corporate approvals.
United Microelectronics Corporation reported higher sales for May 2026 and updated its derivatives positions. May net sales were NT$22,943,755 thousand, up 17.78% from NT$19,480,057 thousand in May 2025. Year-to-date net sales reached NT$106,645,602 thousand, compared with NT$97,793,544 thousand a year earlier, an increase of 9.05%.
The company reported no funds lent to other parties and no endorsements or guarantees for May 2026. It listed financial derivative transactions not under hedging accounting, mainly forward contracts with an unwritten-off notional amount of NT$2,159,010 thousand, a fair value of NT$12,966 thousand, and a net profit from fair value of NT$13,619 thousand, plus a realized loss of NT$743 thousand on written-off forward contracts.
United Microelectronics Corporation plans to issue two unsecured convertible bonds totaling up to NT$16 billion in par value, subject to regulatory approval. The 1st Unsecured Convertible Bond is sized at up to NT$12 billion, while the 2nd Unsecured Convertible Bond is up to NT$4 billion.
Both issues are temporarily structured as five-year, 0%-coupon bonds with a face value of NT$100,000 per bond and no physical certificates, settled by book-entry. Proceeds are earmarked for purchasing machinery and equipment. Detailed conversion, put, and call terms will follow relevant regulations and be finalized by the Chairman or a designee after regulatory approval, with an application planned for OTC trading on the Taipei Exchange.
United Microelectronics Corporation reported two major facility acquisitions and the results of its 2026 annual general meeting. The company agreed to purchase production facilities from L&K Engineering Co., Ltd. (Singapore Branch) for NT$3,476,344,098 and from LIMK Engineering Pte. Ltd. for NT$1,204,169,928, both via price negotiation with non-related counterparties, to support production.
Shareholders approved the 2025 earnings distribution and the 2025 business report and financial statements, with 11,157,922,791 shares represented. Approval rates were about 93.8% for the earnings distribution and 93.7% for the business report. Shareholders also approved amendments to the “Acquisition or Disposal of Assets Procedure” and the issuance of Restricted Stock Awards, the latter receiving 10,389,023,912 votes in favor, or 93.11% of represented shares.
United Microelectronics Corporation filed an update covering upcoming investor outreach and a capital investment. The company plans to attend two institutional investor conferences in Taipei: the “Asia AI Summit 2026” hosted by Morgan Stanley on 2026/05/29, and the “2026 Taiwan Tech Conference” hosted by Citi on 2026/06/05. These events provide management with opportunities to meet investors and discuss the business.
The filing also describes an acquisition of machinery and equipment for production from TOKYO ELECTRON LIMITED, a non-related party. The transaction covers one batch with a total price of NT$1,027,730,259, determined by price negotiation based on market prices. The equipment is intended for production use, with standard purchase-order payment terms and no restrictive covenants noted.
United Microelectronics Corporation reported updated figures for its ongoing share repurchase program. As of 2026/05/20, the company has repurchased 10,020,000 common shares in the current tranche, at a total cost of NTD$1,089,032,948 and an average price of NTD$108.69 per share.
Cumulatively during the repurchase period, UMC now holds 30,551,000 of its own shares, which represents 0.24% of its total issued shares. The company notes that there are no additional matters needing disclosure beyond these buyback statistics.
United Microelectronics Corporation reports progress on its share buyback program, with total repurchased value reaching NTD$406,598,693 as of 2026/05/15. The company has repurchased 3,780,000 common shares at an average price of NTD$107.57 per share.
During the repurchase period, UMC holds 20,531,000 of its own shares, equal to 0.16% of its total issued share count. This update signals ongoing capital return through share repurchases, though the proportion of shares bought back remains relatively small versus total shares issued.
United Microelectronics Corporation reported two capital actions. The company registered a small capital reduction on 2026/05/12 due to cancellation of restricted stock awards, slightly lowering paid-in capital and shares outstanding while nudging book value per share from NT$32.33 to NT$32.34.
UMC also disclosed that its share repurchase program has now exceeded NT$300 million in total value. On 2026/05/13, it had repurchased 6,500,000 common shares for a total of NT$637,759,742 at an average price of NT$98.12 per share, resulting in cumulative treasury shares of 16,751,000, or 0.13% of issued shares.
United Microelectronics Corporation reported updated figures for its ongoing share repurchase program. As of 2026/05/12, the company had most recently repurchased 1,919,000 common shares for a total of NTD$194,882,342, at an average price of NTD$101.55 per share. During the overall repurchase period, UMC held a cumulative total of 10,251,000 of its own shares, representing 0.08% of the company’s issued shares.
United Microelectronics Corporation reports recent progress in its share repurchase program and insider share activity. As of 2026/05/11, the company had most recently repurchased 4,166,000 common shares for a total of NTD$391,855,237, at an average price of NTD$94.06 per share. During the repurchase period, UMC held a cumulative 8,332,000 of its own shares, equal to 0.07% of its issued shares. The filing also includes a monthly report for April 2026 on trading, pledges, and clearance of pledges by directors, executive officers, and 10% shareholders, with the provided tables showing no reported changes in shareholdings or pledged shares.
United Microelectronics Corporation reports April 2026 net sales and related treasury activities. April 2026 net sales were NT$22,663,945 thousand, up from NT$20,454,530 thousand in April 2025, an increase of 10.80%. Year-to-date net sales reached NT$83,701,847 thousand versus NT$78,313,487 thousand a year earlier, a 6.88% rise.
The company reports no funds lent to other parties and no endorsements or guarantees for April 2026. In financial derivative transactions not under hedging accounting, UMC held forwards with unwritten-off trading contracts of NT$1,328,040 thousand, showing a fair value loss of NT$5,456 thousand and a realized loss of NT$1,724 thousand.