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UNITED MICROELECTRONICS CORP (UMC) has a new insider ownership report from CHRO & VP Yen Hung-Yu.
As of September 11, 2026, the reporting officer shows 339,682 Common Shares of beneficial ownership, held directly. This total includes 337,500 shares of a Restricted Stock Award (RSA), with portions scheduled to vest annually on December 5 from 2026 through 2029.
UNITED MICROELECTRONICS CORP (UMC) reported that its chief financial officer and senior vice president, Liu Chitung, sold a total of 1,600,000 Common Shares in mid-September 2026. The sales consisted of 1,200,000 shares on September 16, 2026 at NT$142.333 per share and 400,000 shares on September 17, 2026 at NT$145 per share in open-market or private transactions.
After these transactions, Liu continues to have indirect exposure to UMC through 150,000 Common Shares held by a spouse and 1,000,000 Common Shares held in a CTBC Bank trust. The filing also notes that Liu has 1,126,840 Restricted Stock Awards, with specified portions scheduled to vest annually on December 5 from 2026 to 2029. No Rule 10b5-1 trading plan is reported for these sales.
For UNITED MICROELECTRONICS CORP (UMC), reporting person Liu Chitung, the company’s CFO & SVP, reported ownership changes in Common Shares tied to a trust restructuring on September 7, 2026. A CTBC Bank Trust distributed 1,000,000 shares to Liu, shifting those shares from indirect to direct ownership, bringing his direct holdings to 4,322,917 shares, which include 1,210,000 Restricted Stock Awards. The filing also shows 1,000,000 shares held indirectly through CTBC Bank Trust and 150,000 shares held indirectly by his spouse, and no transactions made under a Rule 10b5-1 trading plan.
United Microelectronics Corporation (UMC) reports that August 2026 net sales were NT$25,044,641 thousand, up from NT$19,159,816 thousand in August 2025, an increase of 30.71%. Year-to-date 2026 net sales were NT$178,659,250 thousand versus NT$155,816,479 thousand a year earlier, a 14.66% increase.
The company states that for August 2026 it had no funds lent to other parties and no endorsements or guarantees outstanding. UMC reports activity in interest rate swap financial derivatives, including unwritten-off trading contracts of NT$1,138,320 thousand, a fair value of NT$9,719 thousand, and a realized loss of NT$33,746 thousand. UMC also plans to attend institutional investor conferences in New York on September 10, 2026, and in Taipei on September 14–15, 2026.
UNITED MICROELECTRONICS CORP (UMC) reports that proceeds from its 2nd domestic unsecured convertible corporate bond issuance have been fully collected. As of September 2, 2026, the collecting bank had received all subscription proceeds totaling NT$4,792,798,780 and remitted the funds to the designated depository bank.
The head office made this disclosure under Paragraph 1, Item 2 of the Regulations Governing the Offering and Issuance of Securities by Securities Issuers and notes that it also meets Article 7, subparagraph 9 of the Securities and Exchange Act Enforcement Rules regarding events with a significant impact on shareholder rights or the price of the company’s securities.
UNITED MICROELECTRONICS CORP (UMC) reports that its board has approved the issuance of the 7th Unsecured Overseas Convertible Bonds, with a total issue size of up to US$1.8 billion. The bonds are tentatively planned to be issued at 100% of face value, carry a 0% coupon, and have a maturity of up to five years. Each bond will have a denomination of US$200,000 or integral multiples of US$100,000 above that amount. The offering will be conducted outside the Republic of China and is subject to approval by the Securities and Futures Bureau of the Financial Supervisory Commission. Proceeds are planned for purchasing machinery, equipment and facilities. Conversion, sell-back, buyback and related pricing and structural terms, including the split between tranche A and tranche B within the US$1.8 billion cap, will be set later by the chairman or a designee based on market conditions, with further announcements to follow.
United Microelectronics Corporation reported a small capital reduction following cancellation of restricted share awards, with paid-in capital moving from NT$125,769,848,700 to NT$125,700,938,990. Shares outstanding decreased from 12,546,433,870 to 12,539,542,899, while book value per share rose slightly from NT$35.38 to NT$35.40.
The company also detailed terms for its 2nd domestic unsecured convertible corporate bond. The base price was set using the average closing price of NT$124.5 per share on the reference date, with a conversion premium rate of 104.98%, resulting in a conversion price of NT$130.7 per share. Separately, a July 2026 insider report shows Senior Vice President Chitung Liu’s holdings decreasing by 1,900,000 shares, and Senior Vice President G C Hung recording a new pledge of 1,200,000 shares.
United Microelectronics Corporation reported July 2026 net sales of 23,844,045 NT$ thousand, an 18.98% increase from July 2025. Year-to-date 2026 net sales were 153,614,609 NT$ thousand, up 12.41% from the same period in 2025.
The company reported no funds lent to other parties and no endorsements or guarantees in July 2026. Financial derivative transactions not designated as hedges consisted of interest rate swaps with 903,000 NT$ thousand in unwritten-off trading contracts, a fair value of (3,179) NT$ thousand, and realized losses of (35,898) NT$ thousand on written-off contracts.
United Microelectronics Corporation announced that for its 1st domestic unsecured convertible corporate bond issuance, the collecting bank has fully received all subscription proceeds totaling NT$12,120,000,000 as of August 5, 2026. These funds have been remitted to the designated depository bank.
The disclosure is made by the head office in accordance with Article 9, Paragraph 1, Item 2 of the Regulations Governing the Offering and Issuance of Securities by Securities Issuers and is stated to meet Article 7, subparagraph 9 of the Securities and Exchange Act Enforcement Rules regarding events that may significantly affect shareholder rights or the price of the securities.
United Microelectronics Corporation reports two corporate actions. First, the company confirms that its 1st domestic unsecured convertible corporate bond has become effective upon filing with the Financial Supervisory Commission, R.O.C. (Taiwan) under FSC Letter No. 1150348929 dated July 17, 2026. The base price for conversion is set using the average closing price over the five business days before July 30, 2026, at NT$121.7 per share, with a conversion premium rate of 119.97%, resulting in a conversion price of NT$146.0 per share.
Second, subsidiary Fortune Venture Capital Corporation disposed of common shares of Centera Photonics Inc. between July 29 and July 30, 2026. The sale covered 870,000 shares at an average unit price of NTD 375.45, for total proceeds of NTD 326,642,500 and a reported gain of NTD 248,883,331. After this transaction, cumulative holdings in Centera Photonics amount to 933,662 shares, valued at NTD 83,449,174, representing 1.40% of the company’s shares, with no restrictions on rights. The ratio of securities investment (including this trade) is 2.42% of total assets and 3.03% of shareholders’ equity, and operational capital stands at NTD 44,980,640,000. The stated purpose of the disposal is financing operations.