UMC Announces Completion of Capital Reduction and Change in Paid-in Capital Registration Due to Cancellation of Restricted Share Employee Rights

1. Date of approval for capital reduction by competent authority: 2026/05/12 2. Date of completion of capital change registration: 2026/05/12 3. Impact on financial statements (including differences in paid-in capital and outstanding shares and impact on net asset value per share): (1) Before capital reduction by cancellation of reacquired restricted share employee rights: The Company's paid-in capital was NT$ 125,785,246,190, outstanding shares were 12,578,524,619 shares, and net asset value per share was NT$ 32.33. (2) After capital reduction by cancellation of reacquired restricted share employee rights: The Company's paid-in capital was NT$ 125,769,848,700, outstanding shares were 12,576,984,870 shares, and net asset value per share was NT$ 32.34. (Note: Net asset value per share is calculated based on the consolidated financial statements reviewed by accountants for Q1 2026.) 4. Planned share exchange operations: Not applicable 5. Number of listed common shares after capital reduction and new share listing: Not applicable 6. Ratio of listed common shares after capital reduction and new share listing to total issued common shares (listed common shares after capital reduction / issued common shares after capital reduction): Not applicable 7. If the number of listed common shares after capital reduction in the preceding two items is less than 60 million shares and less than 25%, please explain the measures to address low share liquidity: Not applicable 8. Other matters that should be specified: None.