Latest Period
Q1 2026
Security Snapshot
Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share (ABOS) Institutional Ownership
CUSIP: 00509G209
13F Institutional Holders and Ownership History from Q3 2021 to Q1 2026
Institutions Reporting
81
Shares (Excl. Options)
43,524,094
Price
$2.36
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- Type / Class
- Equity / Common Stock, $0.0001 par value per share
- Symbol
- ABOS on Nasdaq
- Shares outstanding
- 72,227,200
- Price per share
- $2.81
- All holders as of 31 Mar 2026
- Q1 2026
- Total 13F shares
- 43,524,094
- Total reported value
- $102,695,850
- % of total 13F portfolios
- 0%
- Share change
- +8,937,704
- Value change
- +$21,303,662
- Number of holders
- 81
- Price from insider filings
- $2.81
Reported Shares, Excluding Options vs Price
Reported Value, Excluding Options
Total Investors
Quick Takeaways
- ABOS - Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share is tracked under CUSIP 00509G209.
- 81 institutions reported positions in Q1 2026.
- 4 significant owners is listed from Schedule 13D/13G reporting.
What Changed
- Holder count moved from 70 to 81 between Q4 2025 and Q1 2026.
- Reported value moved from $75,239,476 to $102,695,850.
Why This Matters
- You can quickly see who holds this security, then open quarter and manager detail pages for full evidence.
- 13F and Schedule 13D/13G sections are kept together so you can cross-check institutional and beneficial ownership context.
Source Evidence
Source: SEC Form 13F
Open SEC Evidence
Latest holder context comes from 81 institutions filings for Q1 2026.
Investment Quick Answers
What is CUSIP 00509G209?
CUSIP 00509G209 identifies ABOS - Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share in SEC 13F datasets.
Where can I see the latest institutional holders?
Review the Q1 2026 holders report and the ownership history table below.
Next ownership checks
Use the next link that matches the question you still need to answer about this security.
- Latest 13F filings when you want to inspect fresh institutional portfolio moves.
- Latest Schedule 13D/13G reports when you need large-owner changes outside the 13F cycle.
- All institutional ownership pages to compare this security with other holder-history pages.
Recent Quarterly Holder Reports
Open recent reporting periods for CUSIP 00509G209:
Significant Owners of Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share (ABOS) based on Schedule 13D/G filings
| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | 30% | +19% | $55,075,356 | +$15,883,432 | 21,101,669 | +41% | RA Capital Management, L.P. | 13 Mar 2026 |
| MURRAY JAMES B JR | 5% | $9,425,650 | 3,611,360 | James B. Murray Jr. | 04 Apr 2025 | |||
| Sands Capital Alternatives, LLC | 5.6% | $3,861,295 | 3,417,075 | Sands Capital Alternatives, LLC | 30 Jun 2025 | |||
| FRANKLIN RESOURCES INC | 3.8% | $3,941,714 | 2,305,096 | Franklin Resources, Inc. | 30 Sep 2025 |
As of 31 Mar 2026, 81 institutional investors reported holding 43,524,094 shares of Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share (ABOS). This represents 60% of the company’s total 72,227,200 outstanding shares.
Top 25 Institutional Shareholders
The largest institutional shareholders of Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share (ABOS) together control 58% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | 29% | 20,992,669 | +41% | 0.52% | $49,542,699 |
| Sands Capital Alternatives, LLC | 5.2% | 3,720,105 | +8.9% | 2.1% | $8,779,448 |
| Alyeska Investment Group, L.P. | 3.4% | 2,454,754 | +161% | 0.02% | $5,776,765 |
| FRANKLIN RESOURCES INC | 3.2% | 2,305,096 | 0% | 0% | $5,440,027 |
| Knollwood Investment Advisory, LLC | 2.3% | 1,628,510 | 0% | 0.39% | $3,843,284 |
| VANGUARD CAPITAL MANAGEMENT LLC | 2.1% | 1,506,277 | 0% | 0% | $3,554,814 |
| FMR LLC | 1.6% | 1,157,346 | -43% | 0% | $2,731,337 |
| Ikarian Capital, LLC | 1.5% | 1,053,797 | +314% | 0.36% | $2,486,960 |
| Hudson Bay Capital Management LP | 1.3% | 968,940 | +34% | 0.01% | $2,286,698 |
| Pathstone Holdings, LLC | 1.2% | 859,110 | 0% | 0.01% | $2,027,500 |
| SG Americas Securities, LLC | 1% | 719,257 | +79% | 0% | $1,697,000 |
| MILLENNIUM MANAGEMENT LLC | 0.91% | 659,675 | +13% | 0% | $1,556,833 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | 0.83% | 601,476 | +61% | 0% | $1,419,483 |
| TWO SIGMA INVESTMENTS, LP | 0.73% | 530,812 | +271% | 0% | $1,252,716 |
| Laurion Capital Management LP | 0.73% | 525,444 | -39% | 0.12% | $1,240,048 |
| RENAISSANCE TECHNOLOGIES LLC | 0.66% | 473,946 | +12% | 0% | $1,118,513 |
| GEODE CAPITAL MANAGEMENT, LLC | 0.58% | 416,238 | +1.5% | 0% | $982,755 |
| BOOTHBAY FUND MANAGEMENT, LLC | 0.38% | 273,012 | +590% | 0.02% | $644,308 |
| GOLDMAN SACHS GROUP INC | 0.29% | 206,683 | +75% | 0% | $487,772 |
| VANGUARD FIDUCIARY TRUST CO | 0.28% | 199,226 | 0% | 0% | $470,173 |
| MARSHALL WACE, LLP | 0.27% | 192,889 | +823% | 0% | $455,218 |
| ACADIAN ASSET MANAGEMENT LLC | 0.26% | 185,850 | +22% | 0% | $435,000 |
| BlackRock, Inc. | 0.25% | 178,326 | +5.2% | 0% | $420,849 |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC | 0.24% | 176,171 | +3.5% | 0.01% | $415,764 |
| STATE STREET CORP | 0.21% | 151,728 | +51% | 0% | $358,078 |
Institutional Holders of Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share (ABOS) across Reporting Periods
| Period | Reported Shares, Excl. Options | Value, Excl. Options | Value Change | Price (Median) | Investors |
|---|---|---|---|---|---|
| 2026 Q1 | 43,524,094 | $102,695,850 | +$21,303,662 | $2.36 | 81 |
| 2025 Q4 | 35,659,733 | $75,239,476 | -$34,280 | $2.11 | 70 |
| 2025 Q3 | 35,732,361 | $61,097,340 | -$2,875,631 | $1.71 | 68 |
| 2025 Q2 | 37,585,884 | $43,599,129 | -$2,103,479 | $1.16 | 69 |
| 2025 Q1 | 39,403,584 | $43,344,870 | -$3,628,850 | $1.10 | 79 |
| 2024 Q4 | 42,499,401 | $73,099,738 | -$2,305,406 | $1.72 | 78 |
| 2024 Q3 | 43,605,225 | $107,681,203 | -$212,803 | $2.48 | 72 |
| 2024 Q2 | 43,581,156 | $105,487,337 | -$2,322,503 | $2.42 | 81 |
| 2024 Q1 | 43,364,829 | $175,565,762 | +$20,042,386 | $4.05 | 78 |
| 2023 Q4 | 38,441,008 | $147,599,716 | -$20,522,527 | $3.84 | 67 |
| 2023 Q3 | 43,186,479 | $179,213,677 | +$71,103,757 | $4.15 | 64 |
| 2023 Q2 | 26,328,948 | $126,640,120 | -$5,262,013 | $4.81 | 52 |
| 2023 Q1 | 27,781,261 | $112,787,020 | -$4,579,764 | $4.06 | 61 |
| 2022 Q4 | 28,727,743 | $155,145,749 | -$5,374,332 | $5.40 | 59 |
| 2022 Q3 | 27,496,751 | $275,793,298 | +$19,526,193 | $10.03 | 48 |
| 2022 Q2 | 25,628,401 | $120,458,000 | -$6,031,616 | $4.70 | 44 |
| 2022 Q1 | 27,062,428 | $105,815,702 | -$3,031,020 | $3.91 | 53 |
| 2021 Q4 | 25,569,796 | $172,840,000 | -$1,670,403 | $6.76 | 50 |
| 2021 Q3 | 24,050,108 | $357,352,000 | +$306,574,000 | $14.86 | 40 |