Acumen Pharmaceuticals, Inc. - ABOS
Detailed investor-level table based on 13F positions.
Methodology:
Market value and % of portfolio use SEC reported VALUE ($000).
For PUT/CALL positions this reflects reported underlying exposure, not premium cash paid/received.
Details.
Rows: 0
| Investor | History | Status | Shares held | Market value ($000) | % of portfolio | Previous % | Rank | Change in shares | % change in shares | Source | Date reported |
|---|---|---|---|---|---|---|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | History | Added to | 20,992,669 | 49,542 | 0.52% | 0.32% | 1 | +6,060,606 | 40.59% | Q1 2026 | May 15, 2026 |
| Sands Capital Alternatives, LLC | History | Added to | 3,720,105 | 8,779 | 2.08% | 1.39% | 2 | +303,030 | 8.87% | Q1 2026 | May 08, 2026 |
| Alyeska Investment Group, L.P. | History | Added to | 2,454,754 | 5,776 | 0.02% | 0.01% | 3 | +1,515,151 | 161.25% | Q1 2026 | May 15, 2026 |
| FRANKLIN RESOURCES INC | History | No change | 2,305,096 | 5,440 | 0.0% | 0.0% | 4 | 0 | 0.0% | Q1 2026 | May 13, 2026 |
| ADAR1 Capital Management, LLC | History | Added to | 2,156,334 | 5,088 | 0.3% | 0.14% | 5 | +1,265,151 | 141.96% | Q1 2026 | May 15, 2026 |
| Knollwood Investment Advisory, LLC | History | No change | 1,628,510 | 3,843 | 0.39% | 0.32% | 6 | 0 | 0.0% | Q1 2026 | May 14, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | History | New | 1,506,277 | 3,554 | 0.0% | — | 7 | +1,506,277 | New | Q1 2026 | May 15, 2026 |
| VANGUARD GROUP INC | History | No change | 1,653,772 | 3,489 | 0.0% | 0.0% | 8 | 0 | 0.0% | Q4 2025 | Jan 29, 2026 |
| FMR LLC | History | Reduced | 1,157,346 | 2,731 | 0.0% | 0.0% | 9 | -870,151 | -42.92% | Q1 2026 | May 15, 2026 |
| Ikarian Capital, LLC | History | Added to | 1,053,797 | 2,486 | 0.2% | 0.04% | 10 | +799,485 | 314.37% | Q1 2026 | May 15, 2026 |
| Hudson Bay Capital Management LP | History | Added to | 968,940 | 2,286 | 0.01% | 0.01% | 11 | +243,940 | 33.65% | Q1 2026 | May 13, 2026 |
| Pathstone Holdings, LLC | History | No change | 859,110 | 2,027 | 0.01% | 0.01% | 12 | 0 | 0.0% | Q1 2026 | May 11, 2026 |
| SG Americas Securities, LLC | History | Added to | 719,257 | 1,697 | 0.0% | 0.0% | 13 | +318,210 | 79.34% | Q1 2026 | Apr 16, 2026 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | History | Added to | 713,376 | 1,683 | 0.0% | 0.0% | 14 | +340,178 | 91.15% | Q1 2026 | May 15, 2026 |
| MILLENNIUM MANAGEMENT LLC | History | Added to | 659,675 | 1,556 | 0.0% | 0.0% | 15 | +75,532 | 12.93% | Q1 2026 | May 15, 2026 |
| TWO SIGMA INVESTMENTS, LP | History | Added to | 530,812 | 1,252 | 0.0% | 0.0% | 16 | +387,591 | 270.62% | Q1 2026 | May 15, 2026 |
| Laurion Capital Management LP | History | Reduced | 525,444 | 1,240 | 0.05% | 0.07% | 17 | -341,602 | -39.4% | Q1 2026 | May 14, 2026 |
| RENAISSANCE TECHNOLOGIES LLC | History | Added to | 473,946 | 1,118 | 0.0% | 0.0% | 18 | +50,846 | 12.02% | Q1 2026 | May 14, 2026 |
| GEODE CAPITAL MANAGEMENT, LLC | History | Added to | 416,238 | 982 | 0.0% | 0.0% | 19 | +6,032 | 1.47% | Q1 2026 | May 15, 2026 |
| TWO SIGMA ADVISERS, LP | History | No change | 421,800 | 889 | 0.0% | 0.0% | 20 | 0 | 0.0% | Q4 2025 | Feb 17, 2026 |
| BANK OF AMERICA CORP /DE/ | History | Added to | 320,216 | 755 | 0.0% | 0.0% | 21 | +80,064 | 33.34% | Q1 2026 | May 15, 2026 |
| BOOTHBAY FUND MANAGEMENT, LLC | History | Added to | 273,012 | 644 | 0.01% | 0.0% | 22 | +233,427 | 589.69% | Q1 2026 | May 15, 2026 |
| GOLDMAN SACHS GROUP INC | History | Added to | 206,683 | 487 | 0.0% | 0.0% | 23 | +88,832 | 75.38% | Q1 2026 | May 15, 2026 |
| VANGUARD FIDUCIARY TRUST CO | History | New | 199,226 | 470 | 0.0% | — | 24 | +199,226 | New | Q1 2026 | May 08, 2026 |
| MARSHALL WACE, LLP | History | Added to | 192,889 | 455 | 0.0% | 0.0% | 25 | +171,982 | 822.6% | Q1 2026 | May 14, 2026 |
| ACADIAN ASSET MANAGEMENT LLC | History | Added to | 185,850 | 435 | 0.0% | 0.0% | 26 | +33,070 | 21.65% | Q1 2026 | May 13, 2026 |
| BlackRock, Inc. | History | Added to | 178,326 | 420 | 0.0% | 0.0% | 27 | +8,821 | 5.2% | Q1 2026 | May 13, 2026 |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC | History | Added to | 176,171 | 415 | 0.01% | 0.01% | 28 | +6,000 | 3.53% | Q1 2026 | May 15, 2026 |
| STATE STREET CORP | History | Added to | 151,728 | 358 | 0.0% | 0.0% | 29 | +51,550 | 51.46% | Q1 2026 | May 15, 2026 |
| MORGAN STANLEY | History | Reduced | 144,584 | 341 | 0.0% | 0.0% | 30 | -22,321 | -13.37% | Q1 2026 | May 15, 2026 |
| JANE STREET GROUP, LLC | History | Reduced | 132,261 | 312 | 0.0% | 0.0% | 31 | -9,862 | -6.94% | Q1 2026 | May 12, 2026 |
| Qube Research & Technologies Ltd | History | Added to | 120,388 | 284 | 0.0% | 0.0% | 32 | +72,403 | 150.89% | Q1 2026 | May 15, 2026 |
| DIMENSIONAL FUND ADVISORS LP | History | Added to | 119,756 | 281 | 0.0% | 0.0% | 33 | +70,694 | 144.09% | Q1 2026 | May 07, 2026 |
| CATALYST FINANCIAL PARTNERS LLC | History | No change | 89,699 | 211 | 0.02% | 0.02% | 34 | 0 | 0.0% | Q1 2026 | May 11, 2026 |
| PFG Investments, LLC | History | Added to | 80,850 | 190 | 0.01% | 0.0% | 35 | +61,850 | 325.53% | Q1 2026 | Apr 27, 2026 |
| SIMPLEX TRADING, LLC | History | New | 75,714 | 178 | 0.0% | — | 36 | +75,714 | New | Q1 2026 | May 14, 2026 |
| NORTHERN TRUST CORP | History | No change | 75,212 | 177 | 0.0% | 0.0% | 37 | 0 | 0.0% | Q1 2026 | May 14, 2026 |
| Point72 Asset Management, L.P. | History | Added to | 67,375 | 159 | 0.0% | 0.0% | 38 | +31,010 | 85.27% | Q1 2026 | May 15, 2026 |
| Prospera Financial Services Inc | History | No change | 50,000 | 118 | 0.0% | 0.0% | 39 | 0 | 0.0% | Q1 2026 | Apr 14, 2026 |
| Catalyst Funds Management Pty Ltd | History | Added to | 45,600 | 107 | 0.02% | 0.01% | 40 | +16,000 | 54.05% | Q1 2026 | May 11, 2026 |
| Verdad Advisers, LP | History | New | 37,278 | 87 | 0.1% | — | 42 | +37,278 | New | Q1 2026 | May 15, 2026 |
| UBS Group AG | History | Added to | 37,146 | 87 | 0.0% | 0.0% | 41 | +15,584 | 72.28% | Q1 2026 | May 05, 2026 |
| Rangeley Capital, LLC | History | New | 35,000 | 82 | 0.08% | — | 43 | +35,000 | New | Q1 2026 | May 15, 2026 |
| BARCLAYS PLC | History | Added to | 30,679 | 72 | 0.0% | 0.0% | 44 | +688 | 2.29% | Q1 2026 | May 14, 2026 |
| Intrepid Financial Planning Group LLC | History | No change | 30,150 | 71 | 0.03% | 0.02% | 45 | 0 | 0.0% | Q1 2026 | May 13, 2026 |
| AXQ CAPITAL, LP | History | New | 28,487 | 67 | 0.01% | — | 47 | +28,487 | New | Q1 2026 | May 13, 2026 |
| OMERS ADMINISTRATION Corp | History | Added to | 28,600 | 67 | 0.0% | 0.0% | 46 | +6,146 | 27.37% | Q1 2026 | May 15, 2026 |
| Independent Advisor Alliance | History | No change | 19,000 | 44 | 0.0% | 0.0% | 48 | 0 | 0.0% | Q1 2026 | May 12, 2026 |
| AMERICAN CENTURY COMPANIES INC | History | New | 17,929 | 42 | 0.0% | — | 51 | +17,929 | New | Q1 2026 | May 15, 2026 |
| PINNACLE ASSOCIATES LTD | History | No change | 18,020 | 42 | 0.0% | 0.0% | 49 | 0 | 0.0% | Q1 2026 | Apr 21, 2026 |
| Pinnacle Wealth Management Advisory Group, LLC | History | No change | 18,020 | 42 | 0.0% | 0.0% | 50 | 0 | 0.0% | Q1 2026 | Apr 21, 2026 |
| Factor Wealth Management LTD | History | No change | 16,500 | 38 | 0.01% | 0.01% | 52 | 0 | 0.0% | Q1 2026 | Apr 20, 2026 |
| CAPTRUST FINANCIAL ADVISORS | History | New | 15,757 | 37 | 0.0% | — | 53 | +15,757 | New | Q1 2026 | May 14, 2026 |
| Brevan Howard Capital Management LP | History | New | 15,385 | 36 | 0.0% | — | 54 | +15,385 | New | Q1 2026 | May 15, 2026 |
| Squarepoint Ops LLC | History | New | 15,015 | 35 | 0.0% | — | 55 | +15,015 | New | Q1 2026 | May 15, 2026 |
| HRT FINANCIAL LP | History | New | 13,162 | 31 | 0.0% | — | 56 | +13,162 | New | Q1 2026 | May 14, 2026 |
| JACOBS LEVY EQUITY MANAGEMENT, INC | History | New | 13,011 | 30 | 0.0% | — | 57 | +13,011 | New | Q1 2026 | May 15, 2026 |
| CITADEL ADVISORS LLC | History | Reduced | 12,000 | 28 | 0.0% | 0.0% | 58 | -360,083 | -96.77% | Q1 2026 | May 15, 2026 |
| SEI INVESTMENTS CO | History | New | 11,564 | 27 | 0.0% | — | 59 | +11,564 | New | Q1 2026 | May 13, 2026 |
| Mesirow Financial Investment Management, Inc. | History | New | 11,305 | 26 | 0.0% | — | 60 | +11,305 | New | Q1 2026 | Apr 21, 2026 |
| Schonfeld Strategic Advisors LLC | History | New | 11,300 | 26 | 0.0% | — | 61 | +11,300 | New | Q1 2026 | May 15, 2026 |
| Integrated Wealth Concepts LLC | History | New | 10,179 | 24 | 0.0% | — | 62 | +10,179 | New | Q1 2026 | May 15, 2026 |
| WELLS FARGO & COMPANY/MN | History | Added to | 10,108 | 23 | 0.0% | 0.0% | 63 | +3,008 | 42.37% | Q1 2026 | May 11, 2026 |
| ROYAL BANK OF CANADA | History | Added to | 7,090 | 17 | 0.0% | 0.0% | 64 | +4,808 | 210.69% | Q1 2026 | May 15, 2026 |
| GROUP ONE TRADING LLC | History | Added to | 6,975 | 16 | 0.0% | 0.0% | 65 | +2,223 | 46.78% | Q1 2026 | May 13, 2026 |
| Vanguard Global Advisers, LLC | History | New | 6,684 | 15 | 0.0% | — | 66 | +6,684 | New | Q1 2026 | May 08, 2026 |
| OSAIC HOLDINGS, INC. | History | Reduced | 5,351 | 12 | 0.0% | 0.0% | 67 | -1,500 | -21.89% | Q1 2026 | May 15, 2026 |
| CITIGROUP INC | History | New | 4,486 | 10 | 0.0% | — | 68 | +4,486 | New | Q1 2026 | May 11, 2026 |
| PNC FINANCIAL SERVICES GROUP, INC. | History | No change | 3,080 | 7 | 0.0% | 0.0% | 69 | 0 | 0.0% | Q1 2026 | May 08, 2026 |
| Rockefeller Capital Management L.P. | History | No change | 3,000 | 7 | 0.0% | 0.0% | 70 | 0 | 0.0% | Q1 2026 | May 14, 2026 |
| TFC Financial Management, Inc. | History | No change | 2,500 | 5 | 0.0% | 0.0% | 71 | 0 | 0.0% | Q1 2026 | Apr 23, 2026 |
| JONES FINANCIAL COMPANIES LLLP | History | New | 2,000 | 4 | 0.0% | — | 72 | +2,000 | New | Q1 2026 | May 15, 2026 |
| JPMORGAN CHASE & CO | History | Reduced | 1,444 | 3 | 0.0% | 0.0% | 73 | -965 | -40.06% | Q1 2026 | May 13, 2026 |
| Advisory Services Network, LLC | History | New | 1,111 | 2 | 0.0% | — | 77 | +1,111 | New | Q1 2026 | May 15, 2026 |
| US BANCORP \DE\ | History | New | 1,000 | 2 | 0.0% | — | 76 | +1,000 | New | Q1 2026 | May 14, 2026 |
| BNP PARIBAS FINANCIAL MARKETS | History | Reduced | 1,208 | 2 | 0.0% | 0.0% | 75 | -16 | -1.31% | Q1 2026 | May 12, 2026 |
| NISA INVESTMENT ADVISORS, LLC | History | No change | 1,229 | 2 | 0.0% | 0.0% | 74 | 0 | 0.0% | Q1 2026 | Apr 30, 2026 |
| XTX Topco Ltd | History | Closed out | 0 | 0 | — | 0.0% | — | -49,563 | -100.0% | Q1 2026 | May 15, 2026 |
| Quadrature Capital Ltd | History | Closed out | 0 | 0 | — | 0.0% | — | -49,046 | -100.0% | Q1 2026 | May 15, 2026 |
| Virtu Financial LLC | History | Closed out | 0 | 0 | — | 0.0% | — | -10,922 | -100.0% | Q1 2026 | May 14, 2026 |
| NINE MASTS CAPITAL Ltd | History | Closed out | 0 | 0 | — | 0.0% | — | -10,637 | -100.0% | Q1 2026 | May 12, 2026 |
| Tower Research Capital LLC (TRC) | History | Reduced | 118 | 0 | — | 0.0% | — | -4,339 | -97.35% | Q1 2026 | May 15, 2026 |
| Larson Financial Group LLC | History | Reduced | 20 | 0 | — | 0.0% | — | -4,328 | -99.54% | Q1 2026 | May 15, 2026 |
| FLAGSHIP HARBOR ADVISORS, LLC | History | Closed out | 0 | 0 | — | — | — | -350 | -100.0% | Q1 2026 | Apr 28, 2026 |
| NBT BANK N A /NY | History | Added to | 200 | 0 | — | — | — | +198 | 9900.0% | Q1 2026 | Apr 28, 2026 |
| CWM, LLC | History | Reduced | 87 | 0 | — | — | — | -60 | -40.82% | Q1 2026 | May 14, 2026 |
| SBI Securities Co., Ltd. | History | Reduced | 303 | 0 | — | — | — | -20 | -6.19% | Q1 2026 | Apr 27, 2026 |
| Clearstead Advisors, LLC | History | No change | 60 | 0 | — | — | — | 0 | 0.0% | Q1 2026 | May 06, 2026 |
| Arax Advisory Partners | History | No change | 26 | 0 | — | — | — | 0 | 0.0% | Q1 2026 | May 13, 2026 |
| EverSource Wealth Advisors, LLC | History | No change | 407 | 0 | — | — | — | 0 | 0.0% | Q1 2026 | May 15, 2026 |
| Optiver Holding B.V. | History | No change | 5 | 0 | — | — | — | 0 | 0.0% | Q1 2026 | Jun 02, 2026 |
| Farther Finance Advisors, LLC | History | No change | 200 | 0 | — | — | — | 0 | 0.0% | Q1 2026 | Apr 07, 2026 |