47 institutions reported holding $7.7M of QUANTUM CORP (QMCO) in SEC 13F filings for 2026-03-31. Largest institutional holders: VANGUARD CAPITAL MANAGEMENT LLC ($2.6M), BlackRock, Inc. ($1.0M), GEODE CAPITAL MANAGEMENT, LLC ($756,472), Cygnus Capital Advisors, LLC ($590,000), UBS Group AG ($470,573). Source: SEC Form 13F.
| Rank | Institution | Value | Shares | Change |
|---|---|---|---|---|
| 1 | VANGUARD CAPITAL MANAGEMENT LLC | $2.6M | 539,275 | New |
| 2 | BlackRock, Inc. | $1.0M | 217,532 | Trimmed |
| 3 | GEODE CAPITAL MANAGEMENT, LLC | $756,472 | 159,179 | Added |
| 4 | Cygnus Capital Advisors, LLC | $590,000 | 124,086 | Added |
| 5 | UBS Group AG | $470,573 | 99,068 | Trimmed |
| 6 | VANGUARD FIDUCIARY TRUST CO | $381,249 | 80,263 | New |
| 7 | STATE STREET CORP | $345,867 | 72,814 | Trimmed |
| 8 | SONA ASSET MANAGEMENT (US) LLC | $332,937 | 70,092 | New |
| 9 | MARSHALL WACE, LLP | $178,258 | 37,528 | Added |
| 10 | NORTHERN TRUST CORP | $136,620 | 28,762 | Hold |
| 11 | LPL Financial LLC | $116,841 | 24,598 | Added |
| 12 | PRICE T ROWE ASSOCIATES INC /MD/ | $104,000 | 21,801 | Added |
| 13 | BANK OF AMERICA CORP /DE/ | $97,304 | 20,485 | Trimmed |
| 14 | FLAGSHIP HARBOR ADVISORS, LLC | $81,630 | 17,185 | Trimmed |
| 15 | BRIDGEWAY CAPITAL MANAGEMENT, LLC | $77,140 | 16,240 | New |
| 16 | MORGAN STANLEY | $72,100 | 15,179 | Added |
| 17 | Kovack Advisors, Inc. | $62,774 | 12,480 | New |
| 18 | BARCLAYS PLC | $59,104 | 12,443 | Trimmed |
| 19 | R Squared Ltd | $58,164 | 12,245 | New |
| 20 | XTX Topco Ltd | $53,775 | 11,321 | Trimmed |
| 21 | Vanguard Global Advisers, LLC | $28,500 | 6,000 | New |
| 22 | WELLS FARGO & COMPANY/MN | $19,594 | 4,125 | Added |
| 23 | SBI Securities Co., Ltd. | $9,519 | 2,004 | Trimmed |
| 24 | HOLLENCREST CAPITAL MANAGEMENT | $9,500 | 2,000 | New |
| 25 | JONES FINANCIAL COMPANIES LLLP | $6,866 | 1,467 | Trimmed |
Source: SEC Form 13F filings · as of 2026-03-31