Exhibit 21

QUANTUM CORPORATION

SUBSIDIARIES OF THE REGISTRANT

    1       A.C.N. 120.786.012 Pty. Ltd., an Australian company
2   Advanced Digital Information Corporation, a Washington Corporation
3 Certance (US) Holdings, Inc., a Delaware corporation
4 Certance Holdings Corporation, a Delaware corporation
5 Certance LLC, a Delaware limited liability company
6 Pancetera Software Inc., a Delaware corporation
7 Quantum Beteiligungs GmbH, a German corporation
8 Quantum Boehmenkirch GmbH & Co. KG, a German corporation
9 Quantum Engineering Australia Pty. Ltd., an Australian company
10 Quantum GmbH, a German corporation
11 Quantum India Development Center Private Ltd., an Indian company
12 Quantum International Inc., a Delaware corporation
13 Quantum Korea Co. Ltd., a Korean corporation
14 Quantum Peripherals (Europe) SARL, a Swiss corporation
15 Quantum SARL, a French corporation
16 Quantum Storage Australia Pty. Ltd., an Australian corporation
17 Quantum Storage GmbH, a Swiss corporation
18 Quantum Storage Japan Corporation, a Japanese corporation
19 Quantum Storage Singapore Pte. Ltd., a Singapore private company
20 Quantum Storage UK Ltd., a United Kingdom corporation