QUANTUM CORP /DE/ QMCO
CIK 0000709283 · CUSIP 747906600
Quarter-end disclosures, not live holdings.
Top 20 institutions
Weight means this stock's share of the manager's own portfolio.
| # | Manager | Value | Manager weight | Change vs prior | Source | |
|---|---|---|---|---|---|---|
| 01 | VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history | $2.56M 539,275 shares | 0.00% | — | SEC filing ↗ May 15, 2026 | ▾ |
| 02 | BlackRock, Inc. CIK 2012383 · View history | $1.03M 217,532 shares | 0.00% | -3.21K(-1.5%)Reduced | SEC filing ↗ May 13, 2026 | ▾ |
| 03 | GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history | $756.47K 159,179 shares | 0.00% | +2.31K(+1.5%)Added | SEC filing ↗ May 15, 2026 | ▾ |
| 04 | Cygnus Capital Advisors, LLC CIK 2114319 · View history | $590.00K 124,086 shares | 0.40% | +54.66K(+78.7%)Added | SEC filing ↗ May 13, 2026 | ▾ |
| 05 | UBS Group AG CIK 1610520 · View history | $470.57K 99,068 shares | 0.00% | -66.77K(-40.3%)Reduced | SEC filing ↗ May 5, 2026 | ▾ |
| 06 | VANGUARD FIDUCIARY TRUST CO CIK 933478 · Amended · View history | $381.25K 80,263 shares | 0.00% | — | SEC filing ↗ May 8, 2026 | ▾ |
| 07 | STATE STREET CORP CIK 93751 · View history | $345.87K 72,814 shares | 0.00% | -17.90K(-19.7%)Reduced | SEC filing ↗ May 15, 2026 | ▾ |
| 08 | SONA ASSET MANAGEMENT (US) LLC CIK 1856405 · View history | $332.94K 70,092 shares | 0.01% | +70.09KNew | SEC filing ↗ May 15, 2026 | ▾ |
| 09 | MARSHALL WACE, LLP CIK 1318757 · View history | $178.26K 37,528 shares | 0.00% | +15.79K(+72.6%)Added | SEC filing ↗ May 15, 2026 | ▾ |
| 10 | NORTHERN TRUST CORP CIK 73124 · View history | $136.62K 28,762 shares | 0.00% | 0(0.0%)Unchanged | SEC filing ↗ May 14, 2026 | ▾ |
| 11 | LPL Financial LLC CIK 1403438 · View history | $116.84K 24,598 shares | 0.00% | +6.23K(+33.9%)Added | SEC filing ↗ May 6, 2026 | ▾ |
| 12 | PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history | $104.00K 21,801 shares | 0.00% | +5.90K(+37.1%)Added | SEC filing ↗ May 15, 2026 | ▾ |
| 13 | BANK OF AMERICA CORP /DE/ CIK 70858 · View history | $97.30K 20,485 shares | 0.00% | -50(-0.2%)Reduced | SEC filing ↗ May 18, 2026 | ▾ |
| 14 | FLAGSHIP HARBOR ADVISORS, LLC CIK 1691766 · View history | $81.63K 17,185 shares | 0.00% | -9.40K(-35.4%)Reduced | SEC filing ↗ Apr 28, 2026 | ▾ |
| 15 | BRIDGEWAY CAPITAL MANAGEMENT, LLC CIK 1107261 · View history | $77.14K 16,240 shares | 0.00% | +16.24KNew | SEC filing ↗ May 15, 2026 | ▾ |
| 16 | MORGAN STANLEY CIK 895421 · View history | $72.10K 15,179 shares | 0.00% | +10.87K(+251.9%)Added | SEC filing ↗ May 15, 2026 | ▾ |
| 17 | Kovack Advisors, Inc. CIK 1728321 · View history | $62.77K 12,480 shares | 0.00% | +12.48KNew | SEC filing ↗ May 13, 2026 | ▾ |
| 18 | BARCLAYS PLC CIK 312069 · View history | $59.10K 12,443 shares | 0.00% | -1.75K(-12.4%)Reduced | SEC filing ↗ May 15, 2026 | ▾ |
| 19 | R Squared Ltd CIK 1896148 · View history | $58.16K 12,245 shares | 0.03% | +12.24KNew | SEC filing ↗ Apr 29, 2026 | ▾ |
| 20 | XTX Topco Ltd CIK 1828301 · View history | $53.77K 11,321 shares | 0.00% | -627(-5.2%)Reduced | SEC filing ↗ May 15, 2026 | ▾ |
Showing 20 / 37 institutions. The complete set is available through the API.
Coverage & totals by quarter
Reporting institutions by quarter
Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.
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