Exhibit 21
QUANTUM CORPORATION
SUBSIDIARIES OF THE REGISTRANT
| 1. | ATL Products Ltd., a United Kingdom corporation |
| 2. | Quantum International Inc., a Delaware corporation |
| 3. | Quantum Peripheral Products (Ireland) Ltd., an Ireland corporation |
| 4. | Quantum Peripherals (Europe) Sárl., a Swiss corporation |
| 5. | Quantum Peripherals (Malaysia) Sdn. Bhd., a Malaysian corporation |
| 6. | Quantum Distribution (UK) Limited, a United Kingdom corporation |
| 7. | Quantum Storage Australia Pty. Ltd., an Australian corporation |
| 8. | Quantum Storage Germany GmbH, a German corporation |
| 9. | Quantum Storage France, a French corporation |
| 10. | Quantum Storage Japan Corporation, a Japanese corporation |
| 11. | Quantum Storage Singapore Pte. Ltd., a Singapore private company |
| 12. | Quantum Storage Solutions (M) Sdn. Bhd., a Malaysian corporation |
| 13. | Quantum Storage UK Ltd., a United Kingdom corporation |
| 14. | Certance Holding Corporation, a Delaware corporation |
| 15. | Certance LLC, a Delaware limited liability company |
| 16. | Certance (US) Holdings, Inc., a Delaware corporation |
| 17. | Certance International, a Cayman Islands company |
| 18. | M4 Data (Holdings) Ltd., a UK corporation |
| 19. | Advanced Digital Information Corporation, a Washington Corporation |
| 20. | ADIC AG, a Swiss corporation |
| 21. | Quantum GmbH, a Germany corporation |
| 22. | ADIC Germany GmbH & Co. KG, a Germany corporation |
| 23. | ADIC Germany Beteiligungs GmbH, a Germany corporation |
| 24. | ADIC International Holdings, a Cayman Islands company |
| 25. | ADIC Korea Co. Ltd., a Korean corporation |
| 26. | ADIC Limited, a UK corporation |
| 27. | Quantum SARL, a French corporation |
| 28. | ADIC Manufacturing, LLC, a Delaware company |
| 29. | Mountaingate Imaging Systems Corporation, a Delaware corporation |
| 30. | Pathlight Technology, Inc., a Delaware corporation |
| 31. | ADIC (US) Holdings, a Delaware corporation |
| 32. | A.C.N. 120.786.012 Pty. Ltd., an Australian company |
| 33. | Rocksoft Pty. Ltd., an Australian company |
| 34. | Rocksoft, Inc., a Texas corporation |