DOSSIER · 13F Holders · Q4 2025
QMCO

QUANTUM CORP

40 institutions still hold QUANTUM CORP as of Q4 2025. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.

CUSIP 747906600·40 13F holders·last filed Dec 31, 2025
Market cap
13F value held
$11M
visible holders
Holders
40
filers reporting
Concentration
28.70%
Portolan Capital Management, LLC #1
top holder share
AI Holders Summary · Q4 2025

40 institutions reported QMCO in Q4 2025. Portolan Capital Management, LLC leads at 28.7% of the visible book.

Top holders

Sorted by position value. Source: SEC EDGAR 13F-HR filings.

#HolderValueShares% port.Quarter
01
Portolan Capital Management, LLC
CIK 0001350290
$3M477K0.16%Q4 2025
02
VANGUARD CAPITAL MANAGEMENT LLC
CIK 0002100119· Index
$3M539K0.00%Q1 2026
03
BlackRock, Inc.
CIK 0002012383
$1M218K0.00%Q1 2026
04
GEODE CAPITAL MANAGEMENT, LLC
CIK 0001214717· Index
$756K159K0.00%Q1 2026
05
Cygnus Capital Advisors, LLC
CIK 0002114319
$590K124K0.40%Q1 2026
06
UBS Group AG
CIK 0001610520
$471K99K0.00%Q1 2026
07
VANGUARD FIDUCIARY TRUST CO
CIK 0000933478· Index
$381K80K0.00%Q1 2026
08
STATE STREET CORP
CIK 0000093751
$346K73K0.00%Q1 2026
09
SONA ASSET MANAGEMENT (US) LLC
CIK 0001856405
$333K70K0.01%Q1 2026
10
AlphaQuest LLC
CIK 0001883897
$190K29K0.01%Q4 2025
11
MARSHALL WACE, LLP
CIK 0001318757
$140K22K0.00%Q4 2025
12
NORTHERN TRUST CORP
CIK 0000073124· Index
$137K29K0.00%Q1 2026
13
FLAGSHIP HARBOR ADVISORS, LLC
CIK 0001691766
$121K11K0.00%Q2 2026
14
LPL Financial LLC
CIK 0001403438
$117K25K0.00%Q1 2026
15
PRICE T ROWE ASSOCIATES INC /MD/
CIK 0000080255
$104K22K0.00%Q1 2026
16
BANK OF AMERICA CORP /DE/
CIK 0000070858
$97K20K0.00%Q1 2026
17
BRIDGEWAY CAPITAL MANAGEMENT, LLC
CIK 0001107261
$77K16K0.00%Q1 2026
18
MORGAN STANLEY
CIK 0000895421
$72K15K0.00%Q1 2026
19
Kovack Advisors, Inc.
CIK 0001728321
$63K12K0.00%Q1 2026
20
BARCLAYS PLC
CIK 0000312069
$59K12K0.00%Q1 2026
Page 1 of 2
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Insiders at QUANTUM CORP
Meyrath HuguesNash Laura A.Fichthorn JohnDialectic Technology Spv LlcCraythorne AnthonyBlevins Tony JClancy James CLerner James J