Exhibit 21 SUBSIDIARIES OF REGISTRANT 1. Quantum International, Inc., a California corporation. 2. Quantum International DISC Inc., a California corporation. 3. Quantum Foreign Sales Corporation, a Barbados corporation. 4. Quantum GmbH, a German corporation. 5. Quantum Peripheral Products, Ltd., a United Kingdom corporation. 6. Quantum France SARL, a French corporation. 7. Quantum Asia Pacific Pte., Ltd., a Singapore corporation. 8. La Cie, Ltd., an Oregon corporation. 9. Quantum Peripherals Japan Corporation, a Japanese corporation. 10. Quantum Data Storage B.V., a Netherlands corporation. 11. Quantum Peripheral Products (Ireland), Ltd., an Ireland corporation. 12. Quantum Peripherals (Europe) S.A., a Swiss corporation. 13. Quantum Singapore Pte. Ltd., a Singapore corporation. 14. Quantum Korea Corporation, a Korean corporation. 15. Quantum Hong Kong, Ltd., a Hong Kong corporation. 16. Quantum Peripherals (Malaysia) Sdn. Bhd., a Malaysian corporation. 17. P.T. Quantum Peripherals Indonesia, an Indonesian corporation. 18. Quantum Japan Procurement Center, Inc., a Japanese corporation. 19. Quantum Storage (Malaysia) Sdn. Bhd., a Malaysian corporation. 20. Quantum Peripherals Colorado, Inc., a Delaware corporation.