【CMC Magnetics】Announcement on the Company's Disposal of Marketable Securities

1. Securities Name: ADATA Technology Common Stock 2. Transaction Date: 115/4/23~115/4/28 (April 23-28, 2026) 3. Board of Directors' Resolution Date: Not applicable 4. Other Approval Date: Approval Level: Chairman's approval April 28, 2026 (Republic of China calendar year 115) 5. Transaction Quantity, Unit Price, and Total Transaction Amount: Transaction Quantity (thousand shares): 750 Unit Price (NTD): 441.96 Total Transaction Amount (NTD): 331,467,571 6. Disposal Profit (Not applicable for acquisition of marketable securities): Disposal Profit: NTD 43,320,732 7. Relationship with the Transacting Company: None 8. As of now, the accumulated holdings of these securities (including this transaction), quantity, amount, shareholding ratio, and restricted rights (e.g., pledged status): Remaining holdings: 81,000 shares, Amount: NTD 30,049,687 Shareholding ratio: 0.025%, Restricted rights: None 9. As of now, the proportion of marketable securities investments (including this transaction) listed in Article 3 of the "Regulations Governing the Acquisition and Disposal of Assets by Public Companies" to the total assets and owners' equity attributable to the parent company in the company's latest financial statements, and the amount of working capital in the latest financial statements: Proportion to Total Assets: 76.42% Proportion to Owners' Equity Attributable to Parent Company: 107.04% Working Capital Amount: NTD 8,285,327 thousand 10. Specific Purpose of Acquisition or Disposal: Investment Portfolio 11. Opinions of Dissenting Directors on this Transaction: None 12. Is this a related party transaction: No 13. Counterparty and its relationship with the company: Not applicable 14. Supervisor's approval or Audit Committee's consent date: Not applicable 15. Date of previous major announcement on the same matter: Not applicable 16. Other Explanatory Matters: Authorization was granted on March 31, 2026, to authorized traders to conduct marketable securities transactions in the centralized trading market during the second quarter of 2026.