QMCO Quantum Corp.

NASDAQ
$24.94

Quantum Corp. (QMCO) Institutional Ownership

What the institutions did with QMCO last quarter, from their 13F filings. Counting managers rather than shares is the point: a single index fund adding to a position tells you far less than four hundred separate managers all deciding to. Positions as reported for the quarter ended June 30, 2026.

Managers compared
67
filed both this quarter and last
Managers holding
59
+22 on the quarter
Buyers
48
30 opened new
Sellers
15
8 sold out entirely
Buyer share
76.2%
of managers who traded it
Breadth
+52.4
net buyers, as a share of those trading

Every manager below opens. Subscribers can see any firm's whole portfolio — every position, its weight, and what they bought, trimmed and exited last quarter.

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Ownership map

Each block is one manager, sized by shares held and colored by how much they moved the position last quarter. Green added, red cut, grey stood pat.

Cut Unchanged Added Color saturates at ±50%.

Largest holders

Manager Shares % of reported
Alyeska Investment Group, L.P. 2.7M 18.4%
Two Seas Capital LP 2.5M 17.2%
OAKTREE CAPITAL MANAGEMENT LP 2.0M 13.9%
NEUBERGER BERMAN GROUP LLC 1.2M 8.0%
ASHFORD CAPITAL MANAGEMENT INC 1.0M 7.2%
Portolan Capital Management, LLC 1.0M 7.1%
MARSHALL WACE, LLP 713.1K 4.9%
VANGUARD CAPITAL MANAGEMENT LLC 605.5K 4.2%
Manatuck Hill Partners, LLC 350.0K 2.4%
BlackRock, Inc. 273.0K 1.9%
Cinctive Capital Management LP 182.8K 1.3%
BANK OF AMERICA CORP /DE/ 170.1K 1.2%
GEODE CAPITAL MANAGEMENT, LLC 164.6K 1.1%
RENAISSANCE TECHNOLOGIES LLC 154.5K 1.1%
SONA ASSET MANAGEMENT (US) LLC 150.0K 1.0%
Walleye Capital LLC 120.0K 0.8%
RAYMOND JAMES FINANCIAL INC 103.8K 0.7%
Centiva Capital, LP 100.0K 0.7%
KKM Financial LLC 90.3K 0.6%
VANGUARD FIDUCIARY TRUST CO 89.1K 0.6%
Qube Research & Technologies Ltd 81.0K 0.6%
STATE STREET CORP 75.9K 0.5%
Cygnus Capital Advisors, LLC 74.3K 0.5%
SUSQUEHANNA INTERNATIONAL GROUP, LLP 69.8K 0.5%
Man Group plc 68.6K 0.5%

Largest changes

Manager Action Previous Current Change
Alyeska Investment Group, L.P. New 0 2.7M +2.7M
Two Seas Capital LP New 0 2.5M +2.5M
OAKTREE CAPITAL MANAGEMENT LP New 0 2.0M +2.0M
NEUBERGER BERMAN GROUP LLC New 0 1.2M +1.2M
ASHFORD CAPITAL MANAGEMENT INC New 0 1.0M +1.0M
Portolan Capital Management, LLC New 0 1.0M +1.0M
MARSHALL WACE, LLP Increased 37.5K 713.1K +675.5K
Manatuck Hill Partners, LLC New 0 350.0K +350.0K
Cinctive Capital Management LP New 0 182.8K +182.8K
RENAISSANCE TECHNOLOGIES LLC New 0 154.5K +154.5K
BANK OF AMERICA CORP /DE/ Increased 20.5K 170.1K +149.6K
Walleye Capital LLC New 0 120.0K +120.0K
RAYMOND JAMES FINANCIAL INC New 0 103.8K +103.8K
Centiva Capital, LP New 0 100.0K +100.0K
KKM Financial LLC New 0 90.3K +90.3K
Qube Research & Technologies Ltd New 0 81.0K +81.0K
SONA ASSET MANAGEMENT (US) LLC Increased 70.1K 150.0K +79.9K
SUSQUEHANNA INTERNATIONAL GROUP, LLP New 0 69.8K +69.8K
Man Group plc New 0 68.6K +68.6K
VANGUARD CAPITAL MANAGEMENT LLC Increased 539.3K 605.5K +66.3K
Informed Momentum Co LLC New 0 64.9K +64.9K
BlackRock, Inc. Increased 217.5K 273.0K +55.5K
UBS Group AG Reduced 99.1K 46.1K -53.0K
Cygnus Capital Advisors, LLC Reduced 124.1K 74.3K -49.8K
SEI INVESTMENTS CO New 0 38.7K +38.7K
SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC New 0 34.6K +34.6K
Squarepoint Ops LLC New 0 33.8K +33.8K
LPL Financial LLC Sold Out 24.6K 0 -24.6K
MILLENNIUM MANAGEMENT LLC New 0 21.8K +21.8K
GOLDMAN SACHS GROUP INC New 0 19.2K +19.2K
CITIGROUP INC New 0 14.4K +14.4K
R Squared Ltd Sold Out 12.2K 0 -12.2K
Schonfeld Strategic Advisors LLC New 0 12.1K +12.1K
BARCLAYS PLC Reduced 12.4K 455 -12.0K
XTX Topco Ltd Sold Out 11.3K 0 -11.3K
Invesco Ltd. New 0 10.8K +10.8K
VANGUARD FIDUCIARY TRUST CO Increased 80.3K 89.1K +8.9K
WELLS FARGO & COMPANY/MN Increased 4.1K 11.3K +7.2K
FLAGSHIP HARBOR ADVISORS, LLC Reduced 17.2K 11.0K -6.2K
GEODE CAPITAL MANAGEMENT, LLC Increased 159.2K 164.6K +5.4K
NORTHERN TRUST CORP Increased 28.8K 33.2K +4.5K
JPMORGAN CHASE & CO Increased 8 3.7K +3.7K
PRICE T ROWE ASSOCIATES INC /MD/ Increased 21.8K 25.1K +3.3K
STATE STREET CORP Increased 72.8K 75.9K +3.1K
HOLLENCREST CAPITAL MANAGEMENT Reduced 2.0K 10 -2.0K
Kovack Advisors, Inc. Increased 12.5K 13.4K +950
SBI Securities Co., Ltd. Reduced 2.0K 1.1K -934
BNP PARIBAS FINANCIAL MARKETS Increased 261 1.2K +926
Tower Research Capital LLC (TRC) New 0 655 +655
ROYAL BANK OF CANADA Increased 128 765 +637
OSAIC HOLDINGS, INC. Reduced 965 485 -480
FEDERATED HERMES, INC. Increased 835 1.2K +323
MORGAN STANLEY Increased 15.2K 15.5K +313
HARBOUR INVESTMENTS, INC. New 0 183 +183
JONES FINANCIAL COMPANIES LLLP Increased 1.5K 1.6K +113
FMR LLC New 0 106 +106
NATIONAL BANK OF CANADA /FI/ Sold Out 100 0 -100
Rialto Wealth Management, LLC Sold Out 87 0 -87
Lavaca Capital LLC Sold Out 39 0 -39
Continuum Advisory, LLC New 0 34 +34

13F filings are due 45 days after quarter end and cover long positions in U.S.-listed equities only, so this is a lagged and partial picture: shorts, bonds and foreign listings never appear. Options positions are excluded here rather than folded into the share counts. Political ownership is coming.