Sihwei Navigation Provides TWD 974,333 Thousand Endorsement Guarantee to Subsidiary VALOR

Announcement Date: August 12, 2026 Statement Date: August 11, 2026 Statement Time: 18:44:25 Company Code: 5608 Company Name: Sihwei Navigation Purpose: Notification that the endorsement guarantee provided by the Company to its wholly-owned grandchild company VALOR has reached the disclosure threshold under Article 25, Paragraph 1, Clause 4 of the Handling Principles for Fund Lending and Endorsement Guarantees by Publicly Issued Companies. Applicable Clause: Clause 22 Fact Date: August 11, 2026

Details: 1. Fact Date: 08/11/2026 2. Guaranteed Entity: (1) Company Name: VALOR PESCADORES S.A. PANAMA (2) Relationship with Guarantee Provider: Parent-Subsidiary (3) Endorsement Guarantee Limit (in thousands): 9,721,742 (4) Previous Endorsement Guarantee Balance (in thousands): 0 (5) Amount of New Endorsement Guarantee (in thousands): 974,333 (6) Endorsement Guarantee Balance as of Fact Date (in thousands): 974,333 (7) Actual Drawdown Amount by Guaranteed Entity (in thousands): 0 (8) Reason for New Endorsement Guarantee: Vessel loan financing. 3. Collateral Provided by the Guaranteed Entity: (1) Description: None (2) Value (in thousands): 0 4. Latest Financial Statement of the Guaranteed Entity: (1) Capital (in thousands): 152,880 (2) Accumulated Profit/Loss (in thousands): 144,122 5. Conditions for Release of Endorsement Liability: (1) Condition: Full repayment of vessel loan. (2) Date: Maturity date of bank loan. 6. Total Endorsement Guarantee Limit (in thousands): 58,330,452 7. Endorsement Guarantee Balance as of Fact Date (in thousands): 6,932,369 8. Ratio of Endorsement Guarantee Balance Provided by A to Net Equity in the Latest Financial Statement of the Publicly Issued Company as of Fact Date: 71.31% 9. Combined Ratio of Endorsement Guarantee, Long-Term Investment, and Fund Lending Balances to Net Equity in the Latest Financial Statement of the Publicly Issued Company as of Fact Date: 21.95% 10. Other Disclosures: 1. Figures disclosed converted into New Taiwan Dollars based on exchange rate @32.22. 2. Application for bank endorsement credit line and cancellation of previous endorsement (Re-disclosure on June 9, 2026)