Latest Period
Q2 2026
Security Snapshot
QUANTUM CORP /DE/ - Common Stock, $0.01 par value per share (QMCO) Institutional Ownership
CUSIP: 747906600
13F Institutional Holders and Ownership History from Q3 2024 to Q2 2026
Institutions Reporting
59
Shares (Excl. Options)
14,378,632
Price
$11.00
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- Security type / class
- Equity / Common Stock, $0.01 par value per share
- Symbol
- QMCO on Nasdaq
- All holders as of 30 Jun 2026
- Q2 2026
- Total 13F shares
- 14,378,632
- Total 13F value
- $157,256,442
- Portfolio coverage rank
- 0%
- Share change
- +12,890,365
- Value change
- +$141,187,321
- Number of holders
- 59
- Shares outstanding
- 39,500,556
- SEC-reported price per share
- $11.24
- Insider filing price
- $11.24
Latest holder snapshot
5 signals
Issuer context
Names, identifiers, and filing context for this profile.
3 identity fields
13F Shares, Excluding Options vs Price
13F Value, Excluding Options
Total Investors
Key facts
- QMCO - QUANTUM CORP /DE/ - Common Stock, $0.01 par value per share is tracked under CUSIP 747906600.
- 59 institutions reported positions in Q2 2026.
- 6 significant owners is listed from Schedule 13D/13G reporting.
Change
- Holder count moved from 36 to 59 between Q1 2026 and Q2 2026.
- SEC-reported value moved from $7,655,139 to $157,256,442.
Research use
- You can quickly see who holds this security, then open quarter and manager detail pages for full evidence.
- 13F and Schedule 13D/13G sections are kept together so you can cross-check institutional and beneficial ownership context.
Evidence
Source: SEC Form 13F
Open SEC evidence
Latest holder context comes from 59 institutions filings for Q2 2026.
Security key
747906600
Latest holder period
Q2 2026
13F holders
59
13D/G owners
6
CIK / CUSIP context first
Open Q2 2026 holders
QMCO full holder history
QUANTUM CORP /DE/ SEC filings
QUANTUM CORP /DE/ company facts
QUANTUM CORP /DE/ insider transactions
Broader feeds
Recent Quarterly Holder Reports
Open recent reporting periods for CUSIP 747906600:
13D/G owners
Significant owners
Large-stake holder rows connected to Schedule 13D/G evidence.
Rows
6
Security
QMCO
| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| Dialectic Technology SPV LLC | 40% | -3.4% | $151,021,051 | +$64,381,473 | 16,892,735 | +74% | JOHN FICHTHORN | 04 Jun 2026 |
| Alyeska Investment Group, L.P. | 6.7% | $25,663,484 | 2,653,928 | Alyeska Investment Group, L.P. | 30 Jun 2026 | |||
| Two Seas Capital LP | 6.3% | $24,064,133 | 2,488,535 | Two Seas Capital LP | 30 Jun 2026 | |||
| OAKTREE CAPITAL MANAGEMENT LP | 5.1% | $19,452,926 | 2,011,678 | Oaktree Capital Management LP | 30 Jun 2026 | |||
| VANGUARD GROUP INC | 5% | $2,714,883 | 242,184 | The Vanguard Group | 31 Dec 2024 | |||
| Blue Torch Capital LP | 2.3% | -68% | $1,521,903 | -$3,029,110 | 135,763 | -67% | Blue Torch Capital LP | 13 Feb 2025 |
As of 30 Jun 2026, 59 institutional investors reported holding 14,378,632 shares of QUANTUM CORP /DE/ - Common Stock, $0.01 par value per share (QMCO). This represents 36% of the company’s total 39,500,556 outstanding shares.
13F concentration
Top 25 institutional shareholders
Largest 13F positions for this security by reported shares and value.
Top holder share
35%
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| Alyeska Investment Group, L.P. | 6.7% | 2,653,928 | 0.08% | $29,193,208 | |
| Two Seas Capital LP | 6.3% | 2,488,535 | 1% | $27,373,885 | |
| OAKTREE CAPITAL MANAGEMENT LP | 5.1% | 2,011,678 | 0.42% | $22,128,458 | |
| NEUBERGER BERMAN GROUP LLC | 2.9% | 1,163,315 | 0.01% | $12,796,465 | |
| ASHFORD CAPITAL MANAGEMENT INC | 2.6% | 1,039,200 | 1.1% | $10,551,200 | |
| Portolan Capital Management, LLC | 2.6% | 1,020,120 | 0.42% | $11,221,320 | |
| MARSHALL WACE, LLP | 1.8% | 713,075 | +1800% | 0.01% | $7,843,825 |
| VANGUARD CAPITAL MANAGEMENT LLC | 1.5% | 605,541 | +12% | 0% | $6,660,951 |
| Manatuck Hill Partners, LLC | 0.89% | 350,000 | 1.3% | $3,850,000 | |
| BlackRock, Inc. | 0.69% | 273,030 | +26% | 0% | $3,003,330 |
| Cinctive Capital Management LP | 0.46% | 182,769 | 0.08% | $2,010,459 | |
| BANK OF AMERICA CORP /DE/ | 0.43% | 170,130 | +731% | 0% | $1,871,430 |
| GEODE CAPITAL MANAGEMENT, LLC | 0.42% | 164,600 | +3.4% | 0% | $1,811,524 |
| RENAISSANCE TECHNOLOGIES LLC | 0.39% | 154,516 | 0% | $1,699,676 | |
| SONA ASSET MANAGEMENT (US) LLC | 0.38% | 150,000 | +114% | 0.06% | $1,650,000 |
| Walleye Capital LLC | 0.3% | 120,044 | 0.01% | $1,320,484 | |
| RAYMOND JAMES FINANCIAL INC | 0.26% | 103,836 | 0% | $1,142,196 | |
| Centiva Capital, LP | 0.25% | 100,000 | 0.04% | $1,100,000 | |
| KKM Financial LLC | 0.23% | 90,274 | 0.13% | $960,515 | |
| VANGUARD FIDUCIARY TRUST CO | 0.23% | 89,125 | +11% | 0% | $980,375 |
| Qube Research & Technologies Ltd | 0.21% | 80,977 | 0% | $890,747 | |
| STATE STREET CORP | 0.19% | 75,914 | +4.3% | 0% | $835,054 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | 0.18% | 69,775 | 0% | $767,525 | |
| Man Group plc | 0.17% | 68,593 | 0% | $754,523 | |
| Informed Momentum Co LLC | 0.16% | 64,857 | 0.06% | $713,427 |
Quarter history
Institutional holders across reporting periods
Holder count, reported shares/value, and median price by quarter.
Periods
8
Latest
Q2 2026
Rows shown
1-8 of 8
| Period | 13F Shares, Excl. Options | Value, Excl. Options | Value Change | Price (Median) | Investors |
|---|---|---|---|---|---|
| 2026 Q2 | 14,378,632 | $157,256,442 | +$141,187,321 | $11.00 | 59 |
| 2026 Q1 | 1,610,597 | $7,655,139 | -$3,038,370 | $4.75 | 36 |
| 2025 Q4 | 2,055,041 | $13,255,450 | +$7,188,384 | $6.45 | 39 |
| 2025 Q3 | 865,123 | $8,581,114 | -$227,218 | $9.92 | 28 |
| 2025 Q2 | 884,339 | $8,816,100 | -$12,755,971 | $9.97 | 34 |
| 2025 Q1 | 1,689,433 | $24,295,053 | -$24,451,428 | $14.38 | 29 |
| 2024 Q4 | 1,735,848 | $93,599,486 | +$12,327,384 | $53.92 | 42 |
| 2024 Q3 | 2,274,493 | $7,960,753 | +$7,810,308 | $3.50 | 26 |