ABOS
Acumen Pharmaceuticals, Inc.
Biological Products, (No Diagnostic Substances)Nasdaq<br>Emerging growth company
Total Trades
43
Buys
1
Sells
34
Largest Trade
N/A
Insiders
9
Institutional Funds
53
Inst. Value
$1M+
Activist Filings
14
Insider Trades
| Insider | Title | Type | Value | Shares | Price | Date |
|---|---|---|---|---|---|---|
| Meisner Derek M | Chief Legal Office… | SELL | $15K–$50K | 9K | $3.01 | Mar 4, 2026 |
| Meisner Derek M | Chief Legal Office… | EXERCISE | $15K–$50K | 9K | $1.85 | Mar 4, 2026 |
| Meisner Derek M | Chief Legal Office… | SELL | $50K–$100K | 18K | $3.00 | Jan 29, 2026 |
| Meisner Derek M | Chief Legal Office… | EXERCISE | $15K–$50K | 18K | $1.85 | Jan 29, 2026 |
| Meisner Derek M | Chief Legal Office… | SELL | $15K–$50K | 9K | $1.87 | Jan 23, 2026 |
| Siemers Eric | Chief Medical Offi… | SELL | $1K–$15K | 3K | $1.81 | Jan 23, 2026 |
| Zuga Matt | CFO & Chief Busine… | SELL | $1K–$15K | 4K | $1.83 | Jan 23, 2026 |
| OConnell Daniel Joseph | CEO | SELL | $15K–$50K | 12K | $1.83 | Jan 23, 2026 |
| Barton Russell | COO | SELL | $1K–$15K | 3K | $1.81 | Jan 23, 2026 |
| Zuga Matt | CFO & Chief Busine… | SELL | $1K–$15K | 7K | $1.82 | Jan 12, 2026 |
| Barton Russell | COO | SELL | $1K–$15K | 4K | $1.86 | Jan 12, 2026 |
| Meisner Derek M | Chief Legal Office… | SELL | $50K–$100K | 51K | $1.80 | Jan 12, 2026 |
| OConnell Daniel Joseph | CEO | SELL | $15K–$50K | 26K | $1.77 | Jan 12, 2026 |
| Doherty James J. | President and CDO | SELL | $15K–$50K | 8K | $1.85 | Jan 9, 2026 |
| Schacterle Amy | Chief Regulatory O… | SELL | $1K–$15K | 1K | $1.98 | Jan 9, 2026 |
| Zuga Matt | CFO & Chief Busine… | SELL | $15K–$50K | 15K | $1.97 | Jan 8, 2026 |
| Siemers Eric | Chief Medical Offi… | SELL | $15K–$50K | 11K | $1.96 | Jan 8, 2026 |
| OConnell Daniel Joseph | CEO | SELL | $50K–$100K | 48K | $1.98 | Jan 8, 2026 |
| Meisner Derek M | Chief Legal Office… | SELL | $50K–$100K | 27K | $1.98 | Jan 8, 2026 |
| Barton Russell | COO | SELL | $15K–$50K | 9K | $1.97 | Jan 8, 2026 |
| Zuga Matt | CFO & Chief Busine… | SELL | $50K–$100K | 33K | $1.70 | Jan 24, 2025 |
| OConnell Daniel Joseph | CEO | SELL | $15K–$50K | 13K | $1.59 | Jan 23, 2025 |
| Meisner Derek M | Chief Legal Office… | SELL | $1K–$15K | 3K | $1.59 | Jan 23, 2025 |
| Barton Russell | COO | SELL | $1K–$15K | 3K | $1.61 | Jan 23, 2025 |
| Siemers Eric | Chief Medical Offi… | SELL | $1K–$15K | 3K | $1.59 | Jan 23, 2025 |
| OConnell Daniel Joseph | CEO | GRANT | N/A | 225K | — | Jan 8, 2025 |
| OConnell Daniel Joseph | CEO | SELL | $50K–$100K | 48K | $1.84 | Jan 8, 2025 |
| Meisner Derek M | Chief Legal Office… | GRANT | N/A | 67K | — | Jan 8, 2025 |
| Meisner Derek M | Chief Legal Office… | SELL | $15K–$50K | 11K | $1.84 | Jan 8, 2025 |
| Barton Russell | COO | SELL | $1K–$15K | 8K | $1.86 | Jan 8, 2025 |
| Barton Russell | COO | GRANT | N/A | 50K | — | Jan 8, 2025 |
| Zuga Matt | CFO & Chief Busine… | SELL | $15K–$50K | 13K | $1.84 | Jan 8, 2025 |
| Zuga Matt | CFO & Chief Busine… | GRANT | N/A | 67K | — | Jan 8, 2025 |
| Siemers Eric | Chief Medical Offi… | GRANT | N/A | 67K | — | Jan 8, 2025 |
| Siemers Eric | Chief Medical Offi… | SELL | $15K–$50K | 11K | $1.85 | Jan 8, 2025 |
| OConnell Daniel Joseph | President and CEO | SELL | $50K–$100K | 15K | $3.47 | Jan 20, 2024 |
| Meisner Derek M | Chief Legal Office… | SELL | $15K–$50K | 9K | $3.48 | Jan 20, 2024 |
| Zuga Matt | CFO & Chief Busine… | SELL | $15K–$50K | 4K | $3.71 | Jan 20, 2024 |
| Siemers Eric | Chief Medical Offi… | SELL | $1K–$15K | 3K | $3.71 | Jan 20, 2024 |
| Barton Russell | COO | SELL | $1K–$15K | 3K | $3.73 | Jan 20, 2024 |
| Ives Jeffrey L. | Director | SELL | $100K–$500K | 42K | $6.49 | Aug 18, 2023 |
| Ives Jeffrey L. | Director | EXERCISE | $15K–$50K | 42K | $0.75 | Aug 18, 2023 |
| RA CAPITAL MANAGEMENT, L.P. | Director | BUY | $1M+ | 5.2M | $7.75 | Jul 25, 2023 |
🔓Seeing ranges? Sign in for exact trade values — free forever
Institutional Ownership
13F filings as of Dec 31, 2025 · 53 funds holding
| Fund | Shares | Value | Type |
|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | 14.9M | $1M+ | SH |
| Sands Capital Alternatives, LLC | 3.4M | $1M+ | SH |
| FRANKLIN RESOURCES INC | 2.3M | $1M+ | SH |
| Knollwood Investment Advisory, LLC | 1.6M | $1M+ | SH |
| Alyeska Investment Group, L.P. | 940K | $1M+ | SH |
| ADAR1 Capital Management, LLC | 891K | $1M+ | SH |
| ADAR1 Capital Management, LLC | 891K | $1M+ | SH |
| Laurion Capital Management LP | 867K | $1M+ | SH |
| Pathstone Holdings, LLC | 859K | $1M+ | SH |
| Hudson Bay Capital Management LP | 725K | $1M+ | SH |
| RENAISSANCE TECHNOLOGIES LLC | 423K | $500K+ | SH |
| SG Americas Securities, LLC | 401K | $500K+ | SH |
| GEODE CAPITAL MANAGEMENT, LLC | 341K | $500K+ | SH |
| Ikarian Capital, LLC | 254K | $500K+ | SH |
| ACADIAN ASSET MANAGEMENT LLC | 153K | $100K–$500K | SH |
| STATE STREET CORP | 100K | $100K–$500K | SH |
| CATALYST FINANCIAL PARTNERS LLC | 90K | $100K–$500K | SH |
| MORGAN STANLEY | 90K | $100K–$500K | SH |
| JANE STREET GROUP, LLC | 63K | $100K–$500K | SH |
| GOLDMAN SACHS GROUP INC | 52K | $100K–$500K | SH |
Activist & 5%+ Owners
SC 13D/13G filings — investors holding 5%+ of outstanding shares
SC 13G/A · Nov 4, 2025
3.8%
2.3M shares
Sands Capital Alternatives, LLC
SC 13G/A · Aug 13, 2025
5.6%
3.4M shares
SC 13D/A · Mar 31, 2025
24.8%
15.0M shares
SC 13G/A · Feb 14, 2024
0.0%
0 shares
SC 13G/A · Jan 24, 2024
4.6%
2.7M shares
SC 13D/A · Jul 25, 2023
25.9%
15.0M shares
SC 13G/A · Feb 14, 2023
7.8%
3.2M shares
Sands Capital Ventures Discovery Fund III, L.P.
SC 13G/A · Feb 14, 2023
2.7%
1.1M shares
SC 13G/A · Feb 14, 2023
9.7%
4.0M shares
SC 13G/A · Oct 7, 2022
2.8%
1.1M shares
SC 13G · Feb 16, 2022
8.5%
3.5M shares
SC 13G · Feb 15, 2022
9.9%
4.0M shares
SC 13G · Feb 14, 2022
6.4%
2.6M shares
SC 13G · Jan 27, 2022
6.0%
2.4M shares