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

1. Contract Type: Facility Engineering 2. Event Date: 06/01/2026 ~ 07/02/2026 3. Board Approval Date: Not applicable 4. Other Approval Dates: Approval Level: Approved by General Manager July 2, 2026 (Minguo Year 115) 5. Counterparty and Relationship with Company: Sheng Hui Engineering Technology Co., Ltd., Relationship with Company: None 6. Main Contract Contents (including total contract amount, expected investment amount, contract start and end dates), restrictive clauses, and other important agreements: Total Amount: NT$662,134,000; Contract Period: June 1, 2026 to September 30, 2027; Restrictive Clauses and Other Important Agreements: 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. Directors' Opinions Objecting to This Transaction: None 12. This Transaction is a Related-Party Transaction: No 13. Date of Supervisor Approval or Audit Committee Consent: Not applicable 14. Whether the Appraisal Report is at a Restricted, Specific, or Special Price: No or Not applicable 15. Whether the Appraisal Report Has Not Yet Been Obtained: No or Not applicable 16. Reasons for Not Yet Obtaining the Appraisal Report: Not applicable 17. Reasons for Significant Differences in Appraisal Results and Accountant'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 Date of Material Information Disclosure on the Same Event: Not applicable 22. Other Statements: None