Ruentex Announces Change of Corporate Director Representative

1. Date of Change: 2026/06/23 2. Corporate Name: China Steel Corporation 3. Former Representative: Mr. Liu Hong-Yi 4. Former Representative's Resume: Executive Vice President and Chief Information Security Officer 5. New Representative: Mr. Huang Ching-Yuan 6. New Representative's Resume: Assistant Vice President, Technology Division 7. Reason for Change: Reappointment 8. Original Term: June 12, 2026 to June 11, 2029 9. Effective Date of New Appointment: June 23, 2026 10. Other Matters to be Disclosed: None