Chang Hsin Announces New Factory Construction by Subsidiary Chang Hsin Electronic Materials (Thailand) Co., Ltd. via Self-Land Commissioning at Asian Industrial Park

1. Contract Type: Self-Land Commissioning 2. Event Date: 08/07/115 ~ 08/07/115 3. Board Approval Date: August 7, 2026 (Minguo Year 115) 4. Other Approval Dates: Not applicable 5. Counterparty and Relationship with Company: The transaction party has not been determined. Additional announcements will be made after the formal contract is signed. 6. Main Contents of the Contract (including total contract value, expected investment amount, contract start and end dates, restrictive clauses, and other important terms): Construction works, production line equipment, etc., with an estimated total amount of approximately THB 644,268,530 (approximately TWD 639,790,000). 7. Name of Professional Appraisal 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: Factory construction 11. Dissenting Director's Opinion on This Transaction: None 12. Whether 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 Limited Price, Specific Price, or Special Price: No or Not applicable 15. Whether an Appraisal Report Has 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 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