Quanta Corrects Endorsement and Guarantee Filing Data for June 2025

Disclosure Date: August 18, 2026 Statement Date: August 17, 2026 Statement Time: 14:51:41 Company Code: 2382 Company Name: Quanta Subject: Correction of the Company's Endorsement and Guarantee Filing Data for June 2025 Applicable Clause: Clause 51 Factual Date: August 17, 2026

1. Factual Date: 08/17/2025 2. Company Name: Quanta Computer 3. Relationship with Company (Enter 'Company' or 'Subsidiary'): Company 4. Cross-shareholding Ratio: Not applicable 5. Reason for Occurrence: Supplemental filing of data related to listed subsidiary TMS (4585) 6. Item/Report Name to be Corrected: Detailed Disclosure Table of Endorsement and Guarantee Information Reason: Supplemental filing of data for listed subsidiary TMS (4585) 7. Information Before Correction (Amount/Content/Page): None 8. Information After Correction (Amount/Content/Page): Please refer to page 60 of the Company's Q2 2025 Consolidated Financial Report. https://www.quantatw.com/Quanta/chinese/investment/financials_qr3.aspx 9. Response Measures: Supplemental filing of relevant data 10. Other Matters to be Disclosed: None