QMCO · Quantum Corp /De/

$22.26 -1.30 (-5.52%) At close · Aug 28

Market Cap

$877.27M

39.41M

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Quarter:

Holders: 63

Total Value: $164,612,052

Total Shares: 14,964,732

Institutional Ownership Trend

26 quarters

Superinvestors Holding QMCO

All superinvestors →

Howard Marks $22,128,458

Holder Concentration

Across 63 13F filers · Δ vs Mar 31, 2026

Top Holder

17.7%

−15.7 pts

Top 5

62.5%

−8.2 pts

Top 10

82.3%

−6.4 pts

HHI

991

Broadly held−591

Quarterly Activity

vs Mar 31, 2026

New

Increased

Decreased

Sold Out

Unchanged

Holder count: +26

Institutional value: +2051.5%

Shares held: +829.1%

Top Buyers

vs Mar 31, 2026

Institution	Added	Now Holds
Large MARSHALL WACE, LLP	+675,547	713,075
Mid SONA ASSET MANAGEMENT (US) LLC	+180,008	250,100
Mega BANK OF AMERICA CORP /DE/	+149,645	170,130
Mega VANGUARD CAPITAL MANAGEMENT LLC	+66,266	605,541
Mega BlackRock, Inc.	+55,498	273,030

Top Sellers

vs Mar 31, 2026

Institution	Sold	Now Holds
Mega UBS Group AG	−52,962	46,106
Mega BARCLAYS PLC	−11,988	455
Small FLAGSHIP HARBOR ADVISORS, LLC	−6,181	11,004
Small HOLLENCREST CAPITAL MANAGEMENT	−1,990	10
Mid SBI Securities Co., Ltd.	−934	1,070

Top New Positions

vs Mar 31, 2026

Institution	Acquired	Value (USD)
Large Alyeska Investment Group, L.P.	2,653,928	$29,193,208
Mid Two Seas Capital LP	2,488,535	$27,373,885
Mid OAKTREE CAPITAL MANAGEMENT LP	2,011,678	$22,128,458
Mega NEUBERGER BERMAN GROUP LLC	1,163,315	$12,796,465
Small ASHFORD CAPITAL MANAGEMENT INC	1,039,200	$11,431,200

Top Sold-Out Positions

vs Mar 31, 2026

Institution	Previously Held	Last Value (USD)
Micro Cygnus Capital Advisors, LLC	124,086	$589,408
Mega LPL Financial LLC	24,598	$116,840
Small R Squared Ltd	12,245	$58,163
Mid XTX Topco Ltd	11,321	$53,774
Mega NATIONAL BANK OF CANADA /FI/	100	$475

Filter: New 35 Increased 18 Reduced 6 Sold out 9 Unchanged 4

Showing 68 of 68

All Common Calls Puts

Compact Export CSV

Holder

Value (USD)

% of 13F

Alyeska Investment Group, L.P.

$29,193,208

17.73%

2,653,928

Two Seas Capital LP

$27,373,885

16.63%

2,488,535

OAKTREE CAPITAL MANAGEMENT LP

$22,128,458

13.44%

2,011,678

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
BROOKFIELD Corp /ON/ joint	2,011,678	$22,128,458	100.0%	Defined

NEUBERGER BERMAN GROUP LLC

$12,796,465

7.77%

1,163,315

ASHFORD CAPITAL MANAGEMENT INC

$11,431,200

6.94%

1,039,200

Portolan Capital Management, LLC

$11,221,320

6.82%

1,020,120

MARSHALL WACE, LLP

$7,843,825

4.77%

713,075

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Marshall Wace North America L.P. joint	713,075	$7,843,825	100.0%	Other

VANGUARD CAPITAL MANAGEMENT LLC

$6,660,951

4.05%

605,541

Manatuck Hill Partners, LLC

$3,850,000

2.34%

350,000

BlackRock, Inc.

$3,003,330

1.82%

273,030

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
BLACKROCK FINANCIAL MANAGEMENT INC/DE	9,565	$105,215	3.5%	Sole
BlackRock Investment Management, LLC	2,627	$28,897	1.0%	Sole
BlackRock Fund Advisors	38,870	$427,570	14.2%	Sole
BlackRock Institutional Trust Company, N.A.	221,935	$2,441,285	81.3%	Sole
Aperio Group, LLC	33	$363	0.0%	Sole

Cinctive Capital Management LP

$2,010,459

1.22%

182,769

JANE STREET GROUP, LLC

$1,876,600

1.14%

170,600

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Jane Street Capital, LLC	170,600	$1,876,600	100.0%	Defined

BANK OF AMERICA CORP /DE/

$1,871,430

1.14%

170,130

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
BANK OF AMERICA NA	149,656	$1,646,216	88.0%	Defined
MERRILL LYNCH INTERNATIONAL	20,474	$225,214	12.0%	Defined

GEODE CAPITAL MANAGEMENT, LLC

$1,810,600

1.10%

164,600

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
GEODE CAPITAL MANAGEMENT TRUST COMPANY, LLC	29,646	$326,106	18.0%	Defined
Held directly	134,954	$1,484,494	82.0%	Defined

RENAISSANCE TECHNOLOGIES LLC

$1,699,676

1.03%

154,516

SONA ASSET MANAGEMENT (US) LLC

$1,650,000

1.00%

150,000

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
SONA ASSET MANAGEMENT (UK) LLP	150,000	$1,650,000	100.0%	Other

Walleye Capital LLC

$1,320,484

0.80%

120,044

CITADEL ADVISORS LLC

$1,278,200

0.78%

116,200

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Citadel Securities GP LLC	116,200	$1,278,200	100.0%	Defined

SUSQUEHANNA INTERNATIONAL GROUP, LLP

$1,144,000

0.69%

104,000

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
SUSQUEHANNA SECURITIES, LLC	104,000	$1,144,000	100.0%	Other

RAYMOND JAMES FINANCIAL INC

$1,142,196

0.69%

103,836

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
RAYMOND JAMES & ASSOCIATES	1,010	$11,110	1.0%	Defined
Raymond James Financial Services Advisors, Inc.	3,445	$37,895	3.3%	Defined
ClariVest Asset Management LLC joint	99,381	$1,093,191	95.7%	Defined

SONA ASSET MANAGEMENT (US) LLC

$1,101,100

0.67%

100,100

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
SONA ASSET MANAGEMENT (UK) LLP	100,100	$1,101,100	100.0%	Other

Centiva Capital, LP

$1,100,000

0.67%

100,000

KKM Financial LLC

$993,014

0.60%

90,274

VANGUARD FIDUCIARY TRUST CO

$980,375

0.60%

89,125

Qube Research & Technologies Ltd

$890,747

0.54%

80,977

STATE STREET CORP

$835,054

0.51%

75,914

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
STATE STREET GLOBAL ADVISORS TRUST COMPANY	75,914	$835,054	100.0%	Defined

SUSQUEHANNA INTERNATIONAL GROUP, LLP

$767,525

0.47%

69,775

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
SUSQUEHANNA SECURITIES, LLC	69,775	$767,525	100.0%	Other

Man Group plc

$754,523

0.46%

68,593

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Numeric Investors LLC	68,593	$754,523	100.0%	Defined

Informed Momentum Co LLC

$713,427

0.43%

64,857

UBS Group AG

$507,166

0.31%

46,106

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
UBS Financial Services Inc	125	$1,375	0.3%	Defined
UBS AG	43,159	$474,749	93.6%	Defined
UBS Switzerland AG	2,822	$31,042	6.1%	Defined

SEI INVESTMENTS CO

$426,129

0.26%

38,739

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
SEI INVESTMENTS MANAGEMENT CORP	319	$3,509	0.8%	Sole
SEI TRUST CO	38,420	$422,620	99.2%	Sole

JANE STREET GROUP, LLC

$416,900

0.25%

37,900

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Jane Street Capital, LLC	37,900	$416,900	100.0%	Defined

SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC

$380,611

0.23%

34,601

Squarepoint Ops LLC

$371,987

0.23%

33,817

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Squarepoint Capital LLP	33,817	$371,987	100.0%	Defined

NORTHERN TRUST CORP

$365,420

0.22%

33,220

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
NORTHERN TRUST CO joint	33,220	$365,420	100.0%	Defined

SUSQUEHANNA INTERNATIONAL GROUP, LLP

$289,300

0.18%

26,300

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
SUSQUEHANNA SECURITIES, LLC	26,300	$289,300	100.0%	Other

PRICE T ROWE ASSOCIATES INC /MD/

$275,759

0.17%

25,069

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
T. Rowe Price International Ltd	25,069	$275,759	100.0%	Defined

MILLENNIUM MANAGEMENT LLC

$239,305

0.15%

21,755

CITADEL ADVISORS LLC

$226,600

0.14%

20,600

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Citadel Securities GP LLC	20,600	$226,600	100.0%	Defined

GOLDMAN SACHS GROUP INC

$210,683

0.13%

19,153

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
GOLDMAN SACHS & CO. LLC	19,153	$210,683	100.0%	Defined

BRIDGEWAY CAPITAL MANAGEMENT, LLC

$178,640

0.11%

16,240

MORGAN STANLEY

$170,412

0.10%

15,492

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
MORGAN STANLEY & CO INTERNATIONAL PLC	8	$88	0.1%	Defined
MORGAN STANLEY CAPITAL SERVICES, LLC	351	$3,861	2.3%	Defined
MORGAN STANLEY SMITH BARNEY LLC	15,133	$166,463	97.7%	Defined

CITIGROUP INC

$158,686

0.10%

14,426

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Citigroup Financial Products Inc. joint	14,426	$158,686	100.0%	Defined

Kovack Advisors, Inc.

$147,730

0.09%

13,430

Schonfeld Strategic Advisors LLC

$132,605

0.08%

12,055

WELLS FARGO & COMPANY/MN

$124,300

0.08%

11,300

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
WELLS FARGO CLEARING SERVICES, LLC	11,300	$124,300	100.0%	Defined

FLAGSHIP HARBOR ADVISORS, LLC

$121,044

0.07%

11,004

Invesco Ltd.

$119,229

0.07%

10,839

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Invesco Capital Management LLC	10,839	$119,229	100.0%	Defined

TUDOR INVESTMENT CORP ET AL

$114,400

0.07%

10,400

Vanguard Global Advisers, LLC

$66,000

0.04%

6,000

JPMORGAN CHASE & CO

$40,480

0.02%

3,680

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
JPMorgan Chase Bank, N.A.	3,672	$40,392	99.8%	Defined
J.P. Morgan Securities LLC	8	$88	0.2%	Defined

JONES FINANCIAL COMPANIES LLLP

$17,380

0.01%

1,580

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Edward D. Jones & Co., L.P.	1,580	$17,380	100.0%	Sole

BNP PARIBAS ARBITRAGE, SA

$13,057

0.01%

1,187

FEDERATED HERMES, INC.

$12,738

0.01%

1,158

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
FEDERATED MDTA LLC	1,158	$12,738	100.0%	Defined

SBI Securities Co., Ltd.

$11,770

0.01%

1,070

ROYAL BANK OF CANADA

$8,415

0.01%

765

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
RBC Capital Markets, LLC	765	$8,415	100.0%	Defined

Tower Research Capital LLC (TRC)

$7,205

0.00%

655

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Latour Trading LLC (Latour)	655	$7,205	100.0%	Defined

OSAIC HOLDINGS, INC.

$5,335

0.00%

485

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
OSAIC WEALTH, INC.	10	$110	2.1%	Defined
Osaic Advisory Services, LLC	475	$5,225	97.9%	Defined

BARCLAYS PLC

$5,005

0.00%

455

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
BARCLAYS CAPITAL INC.	455	$5,005	100.0%	Defined

HARBOUR INVESTMENTS, INC.

$2,013

0.00%

183

FMR LLC

$1,166

0.00%

106

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
STRATEGIC ADVISERS LLC	106	$1,166	100.0%	Defined

EFG International AG

$1,100

0.00%

100

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
EFG Private Bank Ltd	100	$1,100	100.0%	Defined

Global Retirement Partners, LLC

$715

0.00%

Continuum Advisory, LLC

$374

0.00%

Quarry LP

$187

0.00%

HOLLENCREST CAPITAL MANAGEMENT

$110

0.00%

Farther Finance Advisors, LLC

$44

0.00%

NewEdge Advisors, LLC

0.00%

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
XTX EXECUTION SERVICES LLC joint	11,321	$53,774	100.0%	Defined

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
National Bank Financial Inc.	100	$475	100.0%	Defined

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Desjardins Securities inc.	25	$118	100.0%	Defined

Key facts CIK 709283 CUSIP 747906600 13F (30d) 62 filings 59 filers Visit website Investor relations