3711 ASE Holding

Disclosure Date: 2026-08-11 Statement Date: 2026-08-10 Statement Time: 17:37:30 Company Code: 3711 Company Name: ASE Holding Subject: Announcement on behalf of subsidiary SPIL Precision Industry Co., Ltd. regarding acquisition of facility engineering Relevant Clause: Item 20 Event Date: 2026-08-10 Details: 1. Type of Contract: Facility Engineering 2. Event Date: 2025-10-28 to 2026-08-10 3. Board Approval Date: Not applicable 4. Other Approval Date: Approval Level: Approved by General Manager Approved on August 10, 2026 (Minguo Year 115) 5. Counterparty and Relationship with Company: Han Hwa Water Treatment Engineering Co., Ltd. Relationship with Company: None 6. Main Contract Contents (including total contract value, estimated investment amount, contract period, restrictions, and other important terms): Total Value: NTD 612,787,500 (approximately USD 20 million) Contract Period: October 28, 2025 to June 30, 2028 Restrictions and Other Important Terms: None 7. Name of Professional Appraisal Firm or Company and Appraisal Results: 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 a Related-Party Transaction? No 13. Date of Supervisor Approval or Audit Committee Consent: Not applicable 14. Is the Appraisal Report at a Restricted, Specific, or Special Price? No or Not applicable 15. Has an Appraisal Report Not Been Obtained? No or Not applicable 16. Reason for Not 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 License Number: Not applicable 21. Previous Date of Material Information Disclosure for the Same Event: Not applicable 22. Other Disclosures: None