QuantumQMCO
13F holders, Q2 2026 (June 30)At the end of Q2 2026, 60 institutions reported holding Quantum Corp. (QMCO) in their 13F filings, up 23 from Q1 2026. 31 opened new positions and 8 sold out. The largest holders were Alyeska Investment Group, L.P. ($29.2M), Two Seas Capital LP ($27.4M) and Oaktree Capital Management ($22.1M). 3 famous investors held it, including Howard Marks (0.6% of Oaktree Capital Management's portfolio), Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio) and Israel Englander (0.0% of Millennium Management's portfolio).
- Company
- Quantum Corp.
- CUSIP
- 747906600
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q1 2026 → Q2 2026
| Institutions | Total Value | |
|---|---|---|
| New Positions | 31 | $130.5M |
| Exits | 8 | $230K |
All 13F filers, Q1 2026 → Q2 2026: 13,014,879 shares bought and 172,714 shares sold, net +12,842,165 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 60 holders
| Alyeska Investment Group, L.P. | 0.08% | New | 2,653,928 | $29.2M |
| Two Seas Capital LP | 1.05% | New | 2,488,535 | $27.4M |
| Oaktree Capital Management | 0.59% | New | 2,011,678 | $22.1M |
| Neuberger Berman Group LLC | 0.01% | New | 1,163,315 | $12.8M |
| Portolan Capital Management, LLC | 0.42% | New | 1,020,120 | $11.2M |
| Ashford Capital Management Inc. | 1.13% | New | 1,039,200 | $10.6M |
| Marshall Wace, LLP | 0.01% | Add +1800.1% | 713,075 | $7.8M |
| Vanguard Capital Management LLC | 0.00% | Add +12.3% | 605,541 | $6.7M |
| Manatuck Hill Partners, LLC | 1.28% | New | 350,000 | $3.9M |
| BlackRock, Inc. | 0.00% | Add +25.5% | 273,030 | $3.0M |
| Cinctive Capital Management LP | 0.08% | New | 182,769 | $2.0M |
| Bank of America Corp. | 0.00% | Add +730.5% | 170,130 | $1.9M |
| Geode Capital Management, LLC | 0.00% | Add +3.4% | 164,600 | $1.8M |
| Renaissance Technologies | 0.00% | New | 154,516 | $1.7M |
| Sona Asset Management (us) LLC | 0.08% | Add +114.0% | 150,000 | $1.6M |
| Walleye Capital LLC | 0.01% | New | 120,044 | $1.3M |
| Raymond James Financial Inc. | 0.00% | New | 103,836 | $1.1M |
| Centiva Capital, LP | 0.04% | New | 100,000 | $1.1M |
| Vanguard Fiduciary Trust Co. | 0.00% | Add +11.0% | 89,125 | $980K |
| KKM Financial LLC | 0.13% | New | 90,274 | $961K |
| Qube Research & Technologies Ltd | 0.00% | New | 80,977 | $891K |
| State Street Corp. | 0.00% | Add +4.3% | 75,914 | $835K |
| Cygnus Capital Advisors, LLC | 0.56% | Reduce -40.1% | 74,323 | $818K |
| Susquehanna International Group, LLP | 0.00% | New | 69,775 | $768K |
| Man Group plc | 0.00% | New | 68,593 | $755K |
| Informed Momentum Co LLC | 0.06% | New | 64,857 | $713K |
| UBS Group AG | 0.00% | Reduce -53.5% | 46,106 | $507K |
| Sei Investments Co. | 0.00% | New | 38,739 | $426K |
| Susquehanna Fundamental Investments, LLC | 0.01% | New | 34,601 | $381K |
| Squarepoint Ops LLC | 0.00% | New | 33,817 | $372K |
| Northern Trust Corp. | 0.00% | Add +15.5% | 33,220 | $365K |
| T. Rowe Price Associates Inc. | 0.00% | Add +15.0% | 25,069 | $276K |
| Millennium Management | 0.00% | New | 21,755 | $239K |
| Goldman Sachs Group Inc. | 0.00% | New | 19,153 | $211K |
| Bridgeway Capital Management, LLC | 0.00% | No change | 16,240 | $179K |
| Morgan Stanley | 0.00% | Add +2.1% | 15,492 | $170K |
| Citigroup Inc. | 0.00% | New | 14,426 | $159K |
| Kovack Advisors, Inc. | 0.01% | Add +7.6% | 13,430 | $147K |
| Schonfeld Strategic Advisors LLC | 0.00% | New | 12,055 | $133K |
| Wells Fargo & Company | 0.00% | Add +173.9% | 11,300 | $124K |
| Flagship Harbor Advisors, LLC | 0.00% | Reduce -36.0% | 11,004 | $121K |
| Invesco Ltd. | 0.00% | New | 10,839 | $119K |
| Vanguard Global Advisers, LLC | 0.00% | No change | 6,000 | $66K |
| JPMorgan Chase & Co. | 0.00% | Add +45900.0% | 3,680 | $44K |
| Jones Financial Companies LLLP | 0.00% | Add +7.7% | 1,580 | $18K |
| BNP Paribas Financial Markets | 0.00% | Add +354.8% | 1,187 | $13K |
| Federated Hermes, Inc. | 0.00% | Add +38.7% | 1,158 | $13K |
| SBI Securities Co., Ltd. | 0.00% | Reduce -46.6% | 1,070 | $12K |
| Royal Bank of Canada | 0.00% | Add +497.7% | 765 | $8K |
| Tower Research Capital LLC (TRC) | 0.00% | New | 655 | $7K |
| Osaic Holdings, Inc. | 0.00% | Reduce -49.7% | 485 | $5K |
| Barclays PLC | 0.00% | Reduce -96.3% | 455 | $5K |
| Harbour Investments, Inc. | 0.00% | New | 183 | $2K |
| FMR LLC | 0.00% | New | 106 | $1K |
| EFG International AG | 0.00% | No change | 100 | $1K |
| Global Retirement Partners, LLC | 0.00% | — | 65 | $715 |
| Continuum Advisory, LLC | 0.00% | New | 34 | $374 |
| Quarry LP | 0.00% | New | 17 | $187 |
| Hollencrest Capital Management | 0.00% | Reduce -99.5% | 10 | $110 |
| Farther Finance Advisors, LLC | 0.00% | No change | 4 | $44 |
"% of holder's portfolio" is QMCO's weight in each manager's 13F, not the share of Quantum Corp. the manager owns.