ASE Holding Announces Subsidiary SPIL's Acquisition of Facility Engineering Project

1. Type of Contract: Facility Engineering 2. Event Date: July 20, 2026 ~ August 5, 2026 (Minguo 115) 3. Board Approval Date: Not applicable 4. Other Decision Dates: Decision Level: Approved by General Manager August 5, 2026 (Minguo 115) 5. Counterparty and Relationship with Company: Saintech Engineering Technology Co., Ltd. Relationship with Company: None 6. Main Contract Contents (including total contract value, expected investment amount, start and end dates), restrictive clauses, and other important terms: Total Amount: NTD 2,046,299,000; Contract Period: July 20, 2026 (Minguo 115) to December 31, 2028 (Minguo 117); Restrictive Clauses and Other Important Terms: None 7. Name of Professional Appraiser Firm or Company and Appraisal Result: Not applicable 8. Name of Real Estate Appraiser: Not applicable 9. License Number of Real Estate Appraiser: Not applicable 10. Specific Purpose of Acquisition: For production and operational use 11. Dissenting Director Opinions on 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 a Limited Price, Specific Price, or Special Price? No or Not applicable 15. Has the Appraisal Report Not Yet Been Obtained? No or Not applicable 16. Reason for Not Yet Obtaining the 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 Accountant: Not applicable 20. Accountant’s License Number: Not applicable 21. Previous Material Information Disclosure Date for the Same Event: Not applicable 22. Other Statements: None