CMC Magnetics (2323) Announcement Regarding Securities Acquisition (Phison)

Announcement Date: May 19, 2026 Company Name: CMC Magnetics

1. Security Name: Phison Common Stock 2. Transaction Date: May 15 - May 19, 2026 3. Board Approval Date: N/A 4. Other Approval Date: Chairman's Approval 5. Quantity, Price, and Total Amount: - Quantity: 245,000 shares - Price per share: 2,618.18 TWD - Total amount: 641,455,127 TWD 6. Gain/Loss: N/A 7. Relationship with Target: None 8. Cumulative Holding Status: - Quantity: 268,000 shares - Amount: 665,317,819 TWD - Holding ratio: 0.12% - Restrictions: None 9. Ratio to Assets: - Ratio to Total Assets: 79.55% - Ratio to Equity attributable to parent owners: 114.25% - Operating Capital: 8,285,327 thousand TWD 10. Purpose: Investment portfolio 11. Dissenting Directors: None 12. Related Party Transaction: No 13. Counterparty Relationship: N/A 14. Auditor Approval Date: N/A 15. Last Disclosure Date: N/A 16. Other: Authorized for trading in securities markets since March 31, 2026.