Derek M. Meisner, Chief Legal Officer and Corporate Secretary at Acumen Pharmaceuticals ($ABOS), made 16 open market sales of company shares over the last year, totaling about $249,000. His most recent sale occurred on March 6, 2026. These transactions rank 7,978th among 11,678 insiders in our database, well below the average sale value of $8.6 million across 6.4 transactions. Meisner reported no open market purchases in this period.
| Transaction Date | Company | Ticker | Insider Name | Title | Transaction Type | Security | Shares | Price | Shares Owned Following | Total Shares Outstanding | % of Owned | % of Outstanding |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| March 6, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | M | Common Stock | 2090 | $1.85 | 176,089.0000 | 60,573,425 | 1.20% | 0.00% |
| March 6, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 2090 | $3.26 | 173,999.0000 | 60,573,425 | 1.19% | 0.00% |
| March 6, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | M | Employee Stock Option (right to buy) | 2090 | $0.00 | 71,048.0000 | 60,573,425 | 2.86% | 0.00% |
| Feb. 27, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | M | Common Stock | 9406 | $1.85 | 183,405.0000 | 60,573,425 | 5.41% | 0.02% |
| Feb. 27, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | M | Employee Stock Option (right to buy) | 9406 | $0.00 | 73,138.0000 | 60,573,425 | 11.40% | 0.02% |
| Feb. 27, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 9406 | $3.01 | 173,999.0000 | 60,573,425 | 5.13% | 0.02% |
| Jan. 26, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | M | Employee Stock Option (right to buy) | 15085 | $0.00 | 85,215.0000 | 60,573,425 | 15.04% | 0.02% |
| Jan. 28, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | M | Employee Stock Option (right to buy) | 2671 | $0.00 | 82,544.0000 | 60,573,425 | 3.13% | 0.00% |
| Jan. 28, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 2671 | $3.00 | 173,999.0000 | 60,573,425 | 1.51% | 0.00% |
| Jan. 28, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | M | Common Stock | 2671 | $1.85 | 176,670.0000 | 60,573,425 | 1.54% | 0.00% |
| Jan. 26, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 15085 | $3.00 | 173,999.0000 | 60,573,425 | 7.98% | 0.02% |
| Jan. 26, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | M | Common Stock | 15085 | $1.85 | 189,084.0000 | 60,573,425 | 8.67% | 0.02% |
| Jan. 22, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 1054 | $1.84 | 179,632.0000 | 60,573,425 | 0.58% | 0.00% |
| Jan. 23, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 5633 | $1.90 | 173,999.0000 | 60,573,425 | 3.14% | 0.01% |
| Jan. 21, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 2247 | $1.81 | 180,686.0000 | 60,573,425 | 1.23% | 0.00% |
| Jan. 16, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | A | Common Stock | 99133 | $0.00 | 182,933.0000 | 60,573,425 | 118.30% | 0.16% |
| Jan. 16, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | A | Employee Stock Option (right to buy) | 148700 | $0.00 | 148,700.0000 | 60,573,425 | 9999.99% | 0.25% |
| Jan. 12, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 8548 | $1.71 | 83,800.0000 | 60,573,425 | 9.26% | 0.01% |
| Jan. 8, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 6819 | $1.82 | 127,640.0000 | 60,573,425 | 5.07% | 0.01% |
| Jan. 8, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 30092 | $1.82 | 97,548.0000 | 60,573,425 | 23.58% | 0.05% |
| Jan. 9, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 5200 | $1.76 | 92,348.0000 | 60,573,425 | 5.33% | 0.01% |
| Jan. 7, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 10070 | $1.99 | 134,459.0000 | 60,573,425 | 6.97% | 0.02% |
| Jan. 7, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 1700 | $1.99 | 144,529.0000 | 60,573,425 | 1.16% | 0.00% |
| Jan. 6, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 3801 | $1.97 | 146,229.0000 | 60,573,425 | 2.53% | 0.01% |
| Jan. 6, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 7097 | $1.97 | 150,030.0000 | 60,573,425 | 4.52% | 0.01% |
| Jan. 5, 2026 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 4000 | $1.96 | 157,127.0000 | 60,573,425 | 2.48% | 0.01% |
| Jan. 21, 2025 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 3418 | $1.59 | 161,127.0000 | 0 | 2.08% | 0.00% |
| Jan. 3, 2025 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 11122 | $1.84 | 97,745.0000 | 0 | 10.22% | 0.00% |
| Jan. 6, 2025 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | A | Employee Stock Option (right to buy) | 100300 | $0.00 | 100,300.0000 | 0 | 9999.99% | 0.00% |
| Jan. 6, 2025 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | A | Common Stock | 66800 | $0.00 | 164,545.0000 | 0 | 68.34% | 0.00% |
| Jan. 19, 2024 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | S | Common Stock | 8933 | $3.48 | 108,867.0000 | 0 | 7.58% | 0.00% |
| Jan. 2, 2024 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | A | Common Stock | 91000 | $0.00 | 117,800.0000 | 0 | 339.55% | 0.00% |
| Jan. 2, 2024 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Officer & Corp Sec | A | Employee Stock Option (right to buy) | 137000 | $0.00 | 137,000.0000 | 0 | 9999.99% | 0.00% |
| Jan. 17, 2023 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Office & Corp Sec | A | Employee Stock Option (right to buy) | 120800 | $0.00 | 120,800.0000 | 0 | 9999.99% | 0.00% |
| Jan. 17, 2023 | Acumen Pharmaceuticals, Inc. | $ABOS | Meisner Derek M | Chief Legal Office & Corp Sec | A | Common Stock | 26800 | $0.00 | 26,800.0000 | 0 | 9999.99% | 0.00% |