🕵️ Acumen Pharmaceuticals, Inc. ($ABOS)
SEC insider & ownership activity, last 12 months · CIK 1576885 · every row links its SEC filing
Over the last 12 months insiders sold $625K with no open-market buying against it. Derek M. Meisner sold $249K through a program of 13 sale notices averaging $19K (Jan–Mar). 2 planned sales are pending, the largest $30K (Derrell Porter). No red-flag 8-Ks in the window.
🚨 22 signals active —
planned-vs-executed verdicts, pre-event flags, and cluster context live in the
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Monthly net open-market insider flow, last 12 months (up = net buying)
Insider flow
0 buyers, $0 (0 lots) · 9 sellers, $625K (48 lots)
| Insider | Buys | Bought | Sells | Sold | Last |
|---|---|---|---|---|---|
| Derek M. Meisner | 0 | – | 16 | $249K | Mar 6, 2026 |
| Oconnell Daniel Joseph | 0 | – | 8 | $163K | Jan 22, 2026 |
| Derrell Porter | 0 | – | 3 | $75K | Jun 17, 2026 |
| Zuga Matt | 0 | – | 7 | $50K | Jan 22, 2026 |
| Barton Russell | 0 | – | 6 | $30K | Jan 22, 2026 |
| Siemers Eric | 0 | – | 4 | $27K | Jan 22, 2026 |
| James J. Doherty | 0 | – | 2 | $15K | Jan 8, 2026 |
| Nathan Fountain | 0 | – | 1 | $14K | Jun 9, 2026 |
| Schacterle Amy | 0 | – | 1 | $2K | Jan 7, 2026 |
5%+ holders
| Holder | Stake | Class | Schedule | Event | |
|---|---|---|---|---|---|
| RA Capital Management, L.P. | 29.5% | 13D | Mar 13, 2026 | filing ↗ | |
| Peter Kolchinsky | 29.5% | 13D | Mar 13, 2026 | filing ↗ | |
| Rajeev Shah | 29.5% | 13D | Mar 13, 2026 | filing ↗ | |
| RA Capital Healthcare Fund, L.P. | 26.8% | 13D | Mar 13, 2026 | filing ↗ | |
| Sands Capital Alternatives, LLC | 5.6% | 13G | Aug 13, 2025 | filing ↗ | |
| Frank M. Sands | 5.6% | 13G | Aug 13, 2025 | filing ↗ | |
| James B. Murray Jr. | 5.0% | 13G | Apr 7, 2026 | filing ↗ |
Planned insider sales (Form 144)
| Seller | Planned | Approx. sale date | |
|---|---|---|---|
| Derrell Porter | $30K | Jun 17, 2026 | filing ↗ |
| Derrell Porter | $30K | Jun 16, 2026 | filing ↗ |
| Derrell Porter | $15K | Jun 15, 2026 | filing ↗ |
| Nathan Fountain | $14K | Jun 9, 2026 | filing ↗ |
| Derek M. Meisner | $7K | Mar 6, 2026 | filing ↗ |
| Derek M. Meisner | $28K | Feb 27, 2026 | filing ↗ |
| Derek M. Meisner | $8K | Jan 28, 2026 | filing ↗ |
| Derek M. Meisner | $45K | Jan 27, 2026 | filing ↗ |
| Derek M. Meisner | $10K | Jan 23, 2026 | filing ↗ |
| Derek M. Meisner | $2K | Jan 22, 2026 | filing ↗ |
| Siemers Eric | $2K | Jan 22, 2026 | filing ↗ |
| Barton Russell | $850 | Jan 22, 2026 | filing ↗ |
| Zuga Matt | $3K | Jan 22, 2026 | filing ↗ |
| Oconnell Daniel Joseph | $5K | Jan 22, 2026 | filing ↗ |
| Derek M. Meisner | $4K | Jan 21, 2026 | filing ↗ |
| Siemers Eric | $4K | Jan 21, 2026 | filing ↗ |
| Barton Russell | $4K | Jan 21, 2026 | filing ↗ |
| Zuga Matt | $4K | Jan 21, 2026 | filing ↗ |
| Oconnell Daniel Joseph | $17K | Jan 21, 2026 | filing ↗ |
| Derek M. Meisner | $15K | Jan 12, 2026 | filing ↗ |
| Oconnell Daniel Joseph | $9K | Jan 12, 2026 | filing ↗ |
| Derek M. Meisner | $9K | Jan 9, 2026 | filing ↗ |
| Oconnell Daniel Joseph | $23K | Jan 9, 2026 | filing ↗ |
| James J. Doherty | $12K | Jan 8, 2026 | filing ↗ |
| Derek M. Meisner | $67K | Jan 8, 2026 | filing ↗ |
| Barton Russell | $7K | Jan 8, 2026 | filing ↗ |
| Zuga Matt | $13K | Jan 8, 2026 | filing ↗ |
| Oconnell Daniel Joseph | $15K | Jan 8, 2026 | filing ↗ |
| Schacterle Amy | $2K | Jan 7, 2026 | filing ↗ |
| James J. Doherty | $3K | Jan 7, 2026 | filing ↗ |
| Derek M. Meisner | $23K | Jan 7, 2026 | filing ↗ |
| Barton Russell | $3K | Jan 7, 2026 | filing ↗ |
| Zuga Matt | $12K | Jan 7, 2026 | filing ↗ |
| Oconnell Daniel Joseph | $75K | Jan 7, 2026 | filing ↗ |
| Derek M. Meisner | $21K | Jan 6, 2026 | filing ↗ |
| Barton Russell | $7K | Jan 6, 2026 | filing ↗ |
| Zuga Matt | $10K | Jan 6, 2026 | filing ↗ |
| Oconnell Daniel Joseph | $10K | Jan 6, 2026 | filing ↗ |
| Siemers Eric | $13K | Jan 5, 2026 | filing ↗ |
| Derek M. Meisner | $8K | Jan 5, 2026 | filing ↗ |
| Siemers Eric | $8K | Jan 5, 2026 | filing ↗ |
| Barton Russell | $8K | Jan 5, 2026 | filing ↗ |
| Zuga Matt | $8K | Jan 5, 2026 | filing ↗ |
| Oconnell Daniel Joseph | $9K | Jan 5, 2026 | filing ↗ |
Material events (8-K)
| Item | Event date | |
|---|---|---|
| Reg FD disclosure (7.01) | Jun 12, 2026 | filing ↗ |
| Other events (8.01) | Jun 12, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jun 12, 2026 | filing ↗ |
| Shareholder vote (5.07) | Jun 3, 2026 | filing ↗ |
| Earnings (2.02) | May 12, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | May 12, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 12, 2026 | filing ↗ |
| Earnings (2.02) | Mar 26, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Mar 26, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Mar 26, 2026 | filing ↗ |
| Material agreement (1.01) | Mar 13, 2026 | filing ↗ |
| Unregistered equity sale (3.02) | Mar 13, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Mar 13, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Mar 13, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Jan 12, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jan 12, 2026 | filing ↗ |
| Earnings (2.02) | Nov 12, 2025 | filing ↗ |
| Reg FD disclosure (7.01) | Nov 12, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Nov 12, 2025 | filing ↗ |
| Officer/director changes (5.02) | Nov 6, 2025 | filing ↗ |
| Reg FD disclosure (7.01) | Nov 6, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Nov 6, 2025 | filing ↗ |
| Earnings (2.02) | Aug 12, 2025 | filing ↗ |
| Reg FD disclosure (7.01) | Aug 12, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Aug 12, 2025 | filing ↗ |