ASE Holding Subsidiary SPIL Announces Acquisition of Facility Engineering Project

1. Contract Type: Facility Engineering 2. Event Date: July 2, 2026 to July 8, 2026 (Minguo Year 115) 3. Board Approval Date: Not applicable 4. Other Approval Dates: Approval Level: Approved by General Manager July 8, 2026 (Minguo Year 115) 5. Counterparty and Relationship with Company: Saintec Limited, Relationship with Company: None 6. Main Contract Contents (including total contract value, expected investment amount, contract start and end dates), restrictions, and other important terms: Total Amount: TWD 678,820,000 Contract Period: July 2, 2026 (Minguo Year 115) to October 31, 2027 (Minguo Year 116) Restrictions and Other Important Terms: None 7. Name of Professional Appraisal Firm or Company and Appraisal Result: Not applicable 8. Name of Real Estate Appraiser: Not applicable 9. Certificate Number of Real Estate Appraiser: Not applicable 10. Specific Purpose of Acquisition: For production and operational use 11. Director Opinions Objecting to This Transaction: None 12. Is This Transaction a Related-Party Transaction: No 13. Date of Supervisor Approval or Audit Committee Consent: Not applicable 14. Is the Appraisal Report at a Limited Price, Specific Price, or Special Price: No or Not applicable 15. Has an Appraisal Report Not Yet Been Obtained: No or Not applicable 16. Reason for Not Yet Obtaining Appraisal Report: Not applicable 17. Reasons for Significant Differences in Appraisal Results and Auditor's Opinion: Not applicable 18. Name of Accounting Firm: Not applicable 19. Name of Auditor: Not applicable 20. Auditor's Certificate Number: Not applicable 21. Previous Date of Material Information Disclosure for the Same Event: Not applicable 22. Other Statements: None