95 institutional investment managers reported ABOS positions in their Form 13F filings for Q2 2026, holding 26,864,093 shares worth $71.7M in total. Sands Capital Alternatives, LLC reported the largest position.

Are funds buying or selling ABOS?

In Q2 2026, 30 managers opened new ABOS positions, 21 added, 15 trimmed and 17 sold out. Managers that filed in both quarters added a net 1,855,744 shares.

How current is this ABOS institutional ownership data?

It covers holdings as of the end of Q2 2026. Managers have 45 days after the quarter ends to file Form 13F (by August 14, 2026 for Q2 2026), so positions may have changed since.

Funds · ABOS

Who owns ABOS?

Institutional ownership of Acumen Pharmaceuticals Inc. from Form 13F, Q2 2026

95 institutional managers reported holding Acumen Pharmaceuticals Inc. (ABOS) in Form 13F filings for Q2 2026, with 26,864,093 shares worth $71.7M. The largest reported holder was Sands Capital Alternatives, LLC. Managers that filed both quarters added a net 1,855,744 shares (+7.4%). 30 opened new positions and 17 sold out.

Funds holding: 95
Value held: $71.7M
New / sold out: 30 / 17
Net shares, same filers: +7.4%

Holdings as of June 30, 2026, the end of Q2 2026. Managers have 45 days after a quarter ends to file Form 13F (by August 14, 2026 for Q2 2026), so positions may have changed since.

Largest holders of ABOS

Fund	Value	Share of 13F holdings	Shares	Move
Sands Capital Alternatives, LLC	$9.9M	13.8%	3,720,105	Unchanged
BlackRock, Inc.	$6.6M	9.3%	2,490,115	Added
Alyeska Investment Group, L.P.	$6.6M	9.1%	2,454,754	Unchanged
Franklin Resources Inc	$6.2M	8.6%	2,305,096	Unchanged
ADAR1 Capital Management, LLC	$5.6M	7.9%	2,111,334	Trimmed
Vanguard Capital Management LLC	$4.5M	6.2%	1,672,072	Added
Knollwood Investment Advisory, LLC	$4.3M	6.1%	1,628,510	Unchanged
Geode Capital Management, LLC	$3.0M	4.3%	1,141,858	Added
Ikarian Capital, LLC	$2.8M	3.9%	1,053,797	Unchanged
Hudson Bay Capital Management LP	$2.5M	3.6%	955,000	Trimmed
Pathstone Holdings, LLC	$2.3M	3.2%	859,110	Unchanged
Renaissance Technologies LLC	$1.8M	2.5%	675,025	Added
Two Sigma Investments, LP	$1.7M	2.3%	622,882	Added
State Street Corp	$1.6M	2.2%	600,528	Added
Northern Trust Corp	$963K	1.3%	360,744	Added
Vanguard Portfolio Management LLC	$857K	1.2%	320,795	New
Dimensional Fund Advisors LP	$779K	1.1%	291,559	Added
Vanguard Fiduciary Trust Co	$778K	1.1%	291,240	Added
Bank of America Corp	$734K	1.0%	274,781	Trimmed
Boothbay Fund Management, LLC	$729K	1.0%	273,012	Unchanged
Acadian Asset Management LLC	$718K	1.0%	270,338	Added
Nomura Holdings Inc	$507K	0.7%	189,712	New
Goldman Sachs Group Inc	$491K	0.7%	183,927	Trimmed
Bridgeway Capital Management, LLC	$470K	0.7%	176,171	Unchanged
Morgan Stanley	$365K	0.5%	136,763	Trimmed

Share of 13F holdings is each fund's shares as a share of the 26,864,093 ABOS shares all 13F filers reported, not of shares outstanding.

Biggest buyers in Q2 2026

BlackRock, Inc. Added+$6.2M
Geode Capital Management, LLC Added+$1.9M
State Street Corp Added+$1.2M
Vanguard Portfolio Management LLC New+$857K
Northern Trust Corp Added+$762K
Renaissance Technologies LLC Added+$537K
Nomura Holdings Inc New+$507K
Dimensional Fund Advisors LP Added+$459K
Vanguard Capital Management LLC Added+$443K
Bank of New York Mellon Corp New+$332K

Biggest sellers in Q2 2026

FMR LLC Trimmed-$3.1M
SG Americas Securities, LLC Sold out-$1.7M
Millennium Management LLC Trimmed-$1.6M
Susquehanna International Group, LLP Trimmed-$1.3M
Laurion Capital Management LP Sold out-$1.2M
Marshall Wace, LLP Trimmed-$387K
Qube Research & Technologies Ltd Trimmed-$218K
Jane Street Group, LLC Sold out-$212K
Point72 Asset Management, L.P. Sold out-$159K
Bank of America Corp Trimmed-$121K

The change in shares since the quarter before, adjusted for stock splits and priced at the Q2 2026 value per share. Funds bought $16.1M and sold $10.7M; 21 added and 15 trimmed.

Schedule 13D and 13G filings on ABOS

Owners of more than 5% must file within days, so these can be newer than the 13F data.

2026-04-07MURRAY JAMES B JR SCHEDULE 13G filed by Acumen Pharmaceuticals Inc.Schedule 13G

Questions about ABOS ownership

Who owns ABOS stock?: 95 institutional investment managers reported ABOS positions in their Form 13F filings for Q2 2026, holding 26,864,093 shares worth $71.7M in total. Sands Capital Alternatives, LLC reported the largest position.
Are funds buying or selling ABOS?: In Q2 2026, 30 managers opened new ABOS positions, 21 added, 15 trimmed and 17 sold out. Managers that filed in both quarters added a net 1,855,744 shares.
How current is this ABOS institutional ownership data?: It covers holdings as of the end of Q2 2026. Managers have 45 days after the quarter ends to file Form 13F (by August 14, 2026 for Q2 2026), so positions may have changed since.

From the SEC's Form 13F data sets for Q2 2026: every 13F holdings report, matched to ABOS by CUSIP. Options are left out. ABOS news and filings · ABOS insider trades · Top funds