Quantum QMCO Institutional Ownership

NASDAQ QMCO

$21.58 -0.67 (-2.99%)

As of: Aug 24, 2026 · 3:59 PM EDT

Institutions by Trading Activity

37 Institutions

Increased 19 51.4%

Unchanged 7 18.9%

Reduced 11 29.7%

Ownership Statistics

13F · as of 31 Mar, 2026

Institutional Ownership

12.71%

▼-2.19 pp QoQ

Shares Held by Institutions

1.61Mn

of 12.67Mn outstanding

▲+87.04% QoQ

Shares Outstanding

12.67Mn

11.06Mn held outside 13F filers

Institutional Investors

filed 13F for Mar 2026

▼-2 vs prior quarter

Net Shares Added (QoQ)

+749.56K

accumulated since last quarter

Value of Holdings

$37.88Mn

reported market value

Shares Owned by Institutions

Shares held % of outstanding

Latest —

Average ownership —

Peak ownership —

Shares Purchased/Sold by Institutions

Accumulated Distributed

Latest quarter —

Net over range —

Accumulating quarters —

Ownership Summary

Quarter ending 31 Mar, 2026

Quantum Corp /De/ (NASDAQ:QMCO) has 37 institutional investors with active 13F positions as of March 2026.

Collectively, these holders controlled 12.7% of Quantum's outstanding shares in March 2026, down from 14.9% in December 2025.
Their total shares held in QMCO increased 87.04% from the prior quarter, while the number of investors in Quantum increased 23.33% year over year.
Of these 37 holders, 19 added to their stakes in Quantum, 11 trimmed positions, and 7 made no changes.
The aggregate institutional position in Quantum amounted to 1.61Mn shares as of March 2026, up by 749.56K shares quarter on quarter, and down 79.71K shares year over year.
VANGUARD CAPITAL MANAGEMENT LLC holds the largest position in QMCO at 539.28K shares as of March 31, 2026, or 4.25% of shares outstanding.
Leading buyers of Quantum shares for the quarter ending March 2026 were VANGUARD CAPITAL MANAGEMENT LLC (539.28K), VANGUARD FIDUCIARY TRUST CO (80.26K), SONA ASSET MANAGEMENT (US) LLC (70.09K), Cygnus Capital Advisors, LLC (54.66K), PRICE T ROWE ASSOCIATES INC /MD/ (21.8K).
The largest sellers of Quantum for the quarter ending March 2026 were UBS Group AG (66.77K), State Street Corp (17.9K), FLAGSHIP HARBOR ADVISORS, LLC (9.4K), BlackRock, Inc. (3.21K), Barclays Plc (1.75K).
Per Business Quant, the top 10 investors in QMCO for the quarter ending March 2026 include VANGUARD CAPITAL MANAGEMENT LLC (539.28K), BlackRock, Inc. (217.53K), GEODE CAPITAL MANAGEMENT, LLC (159.18K), Cygnus Capital Advisors, LLC (124.09K), UBS Group AG (99.07K), VANGUARD FIDUCIARY TRUST CO (80.26K), State Street Corp (72.81K), SONA ASSET MANAGEMENT (US) LLC (70.09K), MARSHALL WACE, LLP (37.53K), Northern Trust Corp (28.76K).

Form 13F Holdings

37 Institutional Holders

Report period 31 Mar, 2026

Total shares held 1.61Mn

Of outstanding 12.71%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	VANGUARD CAPITAL MANAGEMENT LLC	0002100119	539,275	4.25%	▲539,275	0.00%	$2.56Mn
2	BlackRock, Inc.	0002012383	217,532	1.72%	▼3,214	-1.46%	$1.03Mn
3	GEODE CAPITAL MANAGEMENT, LLC	0001214717	159,179	1.26%	▲2,308	+1.47%	$756.47K
4	Cygnus Capital Advisors, LLC	0002114319	124,086	0.98%	▲54,663	+78.74%	$590
5	UBS Group AG	0001610520	99,068	0.78%	▼66,770	-40.26%	$470.57K
6	VANGUARD FIDUCIARY TRUST CO	0000933478	80,263	0.63%	▲80,263	0.00%	$381.25K
7	State Street Corp	0000093751	72,814	0.57%	▼17,900	-19.73%	$345.87K
8	SONA ASSET MANAGEMENT (US) LLC	0001856405	70,092	0.55%	▲70,092	0.00%	$332.94K
9	MARSHALL WACE, LLP	0001318757	37,528	0.30%	▲15,788	+72.62%	$178.26K
10	Northern Trust Corp	0000073124	28,762	0.23%	0	0.00%	$136.62K
11	LPL Financial LLC	0001403438	24,598	0.19%	▲6,234	+33.95%	$116.84K
12	PRICE T ROWE ASSOCIATES INC /MD/	0000080255	21,801	0.17%	▲21,801	0.00%	$104
13	Bank Of America Corp /De/	0000070858	20,485	0.16%	▼50	-0.24%	$97.30K
14	FLAGSHIP HARBOR ADVISORS, LLC	0001691766	17,185	0.14%	▼9,400	-35.36%	$81.63K
15	BRIDGEWAY CAPITAL MANAGEMENT, LLC	0001107261	16,240	0.13%	▲16,240	0.00%	$77.14K
16	Morgan Stanley	0000895421	15,179	0.12%	▲10,866	+251.94%	$72.10K
17	Kovack Advisors, Inc.	0001728321	12,480	0.10%	▲12,480	0.00%	$62.77K
18	Barclays Plc	0000312069	12,443	0.10%	▼1,754	-12.35%	$59.10K
19	R Squared Ltd	0001896148	12,245	0.10%	▲12,245	0.00%	$58.16K
20	XTX Topco Ltd	0001828301	11,321	0.09%	▼627	-5.25%	$53.78K

Showing 1 to 20 of 37 holders