Acumen Pharmaceuticals ABOS Institutional Ownership

NASDAQ ABOS

$2.22 -0.02 (-0.89%)

At close: Sep 30, 2026 · 4:00 PM EDT

Institutions by Trading Activity

98 Institutions

Increased 54 55.1%

Unchanged 29 29.6%

Reduced 15 15.3%

Ownership Statistics

13F · as of 30 Jun, 2026

Institutional Ownership

66.40%

▼-6.37 pp QoQ

Shares Held by Institutions

47.97Mn

of 72.25Mn outstanding

▲+7.95% QoQ

Shares Outstanding

72.25Mn

24.28Mn held outside 13F filers

Institutional Investors

filed 13F for Jun 2026

▲+14 vs prior quarter

Net Shares Added (QoQ)

+3.53Mn

accumulated since last quarter

Value of Holdings

$107.46Mn

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 30 Jun, 2026

Acumen Pharmaceuticals, Inc. (NASDAQ:ABOS) showed up in the 13F filings of 98 institutional investors as of June 2026.

Their combined ownership stood at 66.4% of outstanding shares in June 2026, down from 72.8% in March 2026.
Their total shares held in ABOS increased 7.95% from the prior quarter, while the number of investors in Acumen Pharmaceuticals increased 40.0% year over year.
During the quarter, 54 of these 98 funds increased positions in ABOS, 15 reduced exposure, and 29 held steady.
The aggregate institutional position in Acumen Pharmaceuticals amounted to 47.97Mn shares as of June 2026, up by 3.53Mn shares quarter on quarter, and up 10.51Mn shares year over year.
RA CAPITAL MANAGEMENT, L.P. leads ownership in ABOS with 20.99Mn shares as of June 30, 2026, equal to 29.06% of outstanding shares.
The most significant purchases of ABOS for the quarter ending June 2026 came from BlackRock, Inc. (2.31Mn), GEODE CAPITAL MANAGEMENT, LLC (725.62K), State Street Corp (448.8K), VANGUARD PORTFOLIO MANAGEMENT LLC (320.8K), Northern Trust Corp (285.53K).
Top sellers of ABOS stock for the quarter ending June 2026 included FMR LLC (1.15Mn), MILLENNIUM MANAGEMENT LLC (599.08K), SUSQUEHANNA INTERNATIONAL GROUP, LLP (475.37K), MARSHALL WACE, LLP (144.78K), Qube Research & Technologies Ltd (81.77K).
Per Business Quant data, the top 10 holders of Acumen Pharmaceuticals for the quarter ending June 2026 are RA CAPITAL MANAGEMENT, L.P. (20.99Mn), Sands Capital Alternatives, LLC (3.72Mn), BlackRock, Inc. (2.49Mn), Alyeska Investment Group, L.P. (2.45Mn), Franklin Templeton Inc (2.31Mn), ADAR1 Capital Management, LLC (2.11Mn), VANGUARD CAPITAL MANAGEMENT LLC (1.67Mn), Knollwood Investment Advisory, LLC (1.63Mn), GEODE CAPITAL MANAGEMENT, LLC (1.14Mn), Ikarian Capital, LLC (1.05Mn).

Form 13F Holdings

98 Institutional Holders

Report period 30 Jun, 2026

Total shares held 47.97Mn

Of outstanding 66.40%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	RA CAPITAL MANAGEMENT, L.P.	0001346824	20,992,669	29.06%	0	0.00%	$56.05Mn
2	Sands Capital Alternatives, LLC	0001846444	3,720,105	5.15%	0	0.00%	$9.93Mn
3	BlackRock, Inc.	0002012383	2,490,115	3.45%	▲2,311,789	+1,296.38%	$6.65Mn
4	Alyeska Investment Group, L.P.	0001453072	2,454,754	3.40%	0	0.00%	$6.55Mn
5	Franklin Templeton Inc	0000038777	2,305,096	3.19%	0	0.00%	$6.15Mn
6	ADAR1 Capital Management, LLC	0001940272	2,111,334	2.92%	▼45,000	-2.09%	$5.64Mn
7	VANGUARD CAPITAL MANAGEMENT LLC	0002100119	1,672,072	2.31%	▲165,795	+11.01%	$4.46Mn
8	Knollwood Investment Advisory, LLC	0001999346	1,628,510	2.25%	0	0.00%	$4.35Mn
9	GEODE CAPITAL MANAGEMENT, LLC	0001214717	1,141,858	1.58%	▲725,620	+174.33%	$3.05Mn
10	Ikarian Capital, LLC	0001778253	1,053,797	1.46%	0	0.00%	$2.81Mn
11	Hudson Bay Capital Management LP	0001393825	955,000	1.32%	▼13,940	-1.44%	$2.55Mn
12	Pathstone Holdings, LLC	0002011612	859,110	1.19%	0	0.00%	$2.29Mn
13	RENAISSANCE TECHNOLOGIES LLC	0001037389	675,025	0.93%	▲201,079	+42.43%	$1.80Mn
14	TWO SIGMA INVESTMENTS, LP	0001179392	622,882	0.86%	▲92,070	+17.35%	$1.66Mn
15	State Street Corp	0000093751	600,528	0.83%	▲448,800	+295.79%	$1.60Mn
16	Northern Trust Corp	0000073124	360,744	0.50%	▲285,532	+379.64%	$963.19K
17	VANGUARD PORTFOLIO MANAGEMENT LLC	0002100121	320,795	0.44%	▲320,795	0.00%	$856.52K
18	DIMENSIONAL FUND ADVISORS LP	0000354204	291,559	0.40%	▲171,803	+143.46%	$778.97K
19	VANGUARD FIDUCIARY TRUST CO	0000933478	291,240	0.40%	▲92,014	+46.19%	$777.61K
20	Bank Of America Corp /De/	0000070858	274,781	0.38%	▼45,435	-14.19%	$733.67K

Showing 1 to 20 of 98 holders