3711 ASE Holding

Announcement Date: June 26, 2026 Statement Date: June 25, 2026 Statement Time: 16:48:47 Company Code: 3711 Company Name: ASE Holding Corporation Subject: The company's board of directors has resolved to issue its first overseas unsecured convertible corporate bond Applicable Clause: Clause 11 Factual Date: June 25, 2026

Details: 1. Board Resolution Date: June 25, 2026 2. Name (Name of the Xth secured/unsecured corporate bond issued by XX Company): ASE Holding Corporation's First Overseas Unsecured Convertible Corporate Bond for Year 2026 3. Is the issuance of corporate bonds under a blanket registration (Yes/No): No 4. Total Issuance Amount: Tentatively capped at USD 1 billion 5. Face Value per Note: USD 200,000, or if exceeding USD 200,000, in multiples of USD 100,000 6. Issue Price: Issued at 100% of face value 7. Issuance Period: Tentatively set at 5 years 8. Issue Interest Rate: Tentatively set at 0% per annum 9. Type, Name, Amount, and Terms of Collateral: Not applicable 10. Use and Allocation Plan of Raised Funds: Subscription to new shares issued through cash capital increase by subsidiaries ASE Semiconductor Manufacturing Corporation and SPIL Precision Industries Corporation 11. Underwriting Method: The bonds will be issued outside the Republic of China and handled in accordance with the laws, regulations, and international market practices of the sales jurisdictions. All bonds will be publicly offered. 12. Bond Trustee: Citicorp International Limited 13. Underwriter or Distributor: International Lead Underwriters: DBS Bank Ltd., Goldman Sachs International, The Hongkong and Shanghai Banking Corporation Limited Domestic Lead Underwriter: KGI Securities Co., Ltd. 14. Issuance Guarantor: Not applicable 15. Agent for Principal and Interest Payment: Citibank, N.A., London Branch 16. Certification Institution: Not applicable 17. Conversion Mechanism for Convertible Securities: To be determined by the Chairman or Group CFO based on actual market conditions 18. Put Option Terms: To be determined by the Chairman or Group CFO based on actual market conditions 19. Call Option Terms: To be determined by the Chairman or Group CFO based on actual market conditions 20. Share Conversion Benchmark Date for Convertible, Exchangeable, or Subscription Rights-Attached Securities: To be determined by the Chairman or Group CFO based on actual market conditions 21. Potential Equity Dilution from Conversion, Exchange, or Subscription: To be determined based on the actual conversion premium rate at issuance 22. Rationality and Necessity of Fundraising Following Cash Capital Reduction (applicable if cash capital reduction was conducted in the current or prior year): Not applicable 23. Other Matters to be Disclosed: a. The key terms of this overseas unsecured convertible bond, including issuance method, project plans, actual issuance and fundraising amount, coupon rate, scheduled progress, and expected benefits, are authorized to be determined by the Chairman or Group CFO based on actual market conditions. Adjustments may be made as required by regulatory authorities, operational assessments, or objective needs. Actual issuance terms will be reported to the shareholders' meeting upon completion. b. To facilitate the issuance, the Chairman or Group CFO and/or their designated representatives are authorized to approve and sign all relevant contracts, documents, and handle all related matters. c. For any unaddressed matters related to this issuance, the Chairman or Group CFO is fully authorized to handle them in accordance with applicable laws.