www.umc.com
Exhibit
Exhibit Description
99.1 Announcement on 2025/11/24: To clarify news reported by Commercial Times on November 22, 2025
99.2 Announcement on 2025/11/26: Supplement to the unsecured straight corporate bond issuance authorized by the Board of Director resolution passed on April 23rd, 2025 1. Date of occurrence of the event: 2025/11/24
Exhibit 99.1
To clarify news reported by Commercial Times on November 22, 2025
2. Company name: UNITED MICROELECTRONICS CORP.
3. Relationship with the Company (please enter “the company itself” or “subsidiaries”): the company itself
4. Reciprocal shareholding percentage: N/A
5. Name of the reporting media: Commercial Times, B01
6. Content of the report:
Specialty technology process booming for UMC, the momentum expected to continue into next year.
7. Cause of occurrence:
The Company does not comment on speculative reports or market rumors.
8. Countermeasures: None
9. Any other matters that need to be specified: None 1. Date of the board of directors’ resolution: NA
Exhibit 99.2
Supplement to the unsecured straight corporate bond issuance authorized by the Board of Director resolution passed on April 23rd, 2025
2. Name [issue no.__ of (secured, unsecured) corporate bonds of ___________ (company)]:
United Microelectronics Corporation 4th unsecured straight corporate bond issuance in 2025
3. Whether to adopt shelf registration (Yes/No): No
4. Total amount issued:
NT$4,800 million;3 years period NT$2,300 million, 5 years period NT$2,500 million
5. Face value per bond: NT$1 million
6. Issue price: At par
7. Issuance period:3 years, 5 years
8. Coupon rate: Fixed rate, 3 years 1.55% p.a., 5 years 1.60% p.a.
9. Types, names, monetary values and stipulations of collaterals: N/A
10. Use of the funds raised by the offering and utilization plan: Debt Repayment
11. Underwriting method: Public offering through underwriters
12. Trustees of the corporate bonds: CTBC Bank Co., Ltd
13. Underwriter or agent: Masterlink Securities Co., Ltd as the lead underwriter
14. Guarantor(s) for the issuance: None
15. Agent for payment of the principal and interest: CTBC Bank Co., Ltd
16. Certifying institution: None
17. Where convertible into shares, the rules for conversion: N/A
18. Sell-back conditions: None
19. Buyback conditions: None
20. Reference date for any additional share exchange, stock swap, or subscription: N/A
21. Possible dilution of equity in case of any additional share exchange, stock swap, or subscription: N/A
22. Any other matters that need to be specified: None