Across the past 12 months, Prime Medicine insiders reported no open-market purchases or sales.
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | David R. Liu | TenPercentOwner | 20,240,945 | 0 | 20,240,945 | 30.2% | 01 Jul, 2025 |
| 2 | 2019 Gp, L.L.C. Gv | TenPercentOwner | 0 | 10,100,058 | 10,100,058 | 15.1% | 22 Jun, 2023 |
| 3 | Llc Fmr | Other | 0 | 8,462,946 | 8,462,946 | 12.6% | 26 Oct, 2022 |
| 4 | Venture Partners Xii, Llc Arch | TenPercentOwner | 0 | 6,230,300 | 6,230,300 | 9.3% | 01 Aug, 2025 |
| 5 | Robert Nelsen | Director, TenPercentOwner | 0 | 6,230,300 | 6,230,300 | 9.3% | 01 Aug, 2025 |
| 6 | Venture Partners X, Llc Arch | TenPercentOwner | 0 | 6,230,300 | 6,230,300 | 9.3% | 01 Aug, 2025 |
| 7 | Thomas Cahill | Director | 0 | 5,305,679 | 5,305,679 | 7.9% | 26 Oct, 2022 |
| 8 | 2021 Gp, L.L.C. Gv | TenPercentOwner | 0 | 3,262,440 | 3,262,440 | 4.9% | 05 Aug, 2025 |
| 9 | Keith Michael Gottesdiener | Director, Officer | 0 | 732,500 | 732,500 | 1.1% | 10 Oct, 2024 |
| 10 | Allan Reine | Chief Executive Officer | 125,000 | 0 | 125,000 | 0.2% | 22 May, 2025 |
| 11 | Ann L. Lee | Chief Technical Officer | 100,000 | 0 | 100,000 | 0.1% | 22 May, 2025 |
| 12 | Richard Brudnick | Chief Business Officer | 20,000 | 0 | 20,000 | 0.0% | 22 May, 2025 |
Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.
| Date | Insider | Position | Transaction | Shares | Price | Value | Shares Held After | Ownership |
|---|---|---|---|---|---|---|---|---|
| 05 Jun, 2026 | Jeffrey D Marrazzo | Director | Acquired A | 75,000 | $0.00 | $0 | 75,000 | Direct |
| 05 Jun, 2026 | Wendy Chung | Director | Acquired A | 75,000 | $0.00 | $0 | 75,000 | Direct |
| 05 Jun, 2026 | Kaye I Foster-Cheek | Director | Acquired A | 75,000 | $0.00 | $0 | 75,000 | Direct |
| 05 Jun, 2026 | David P Schenkein | Director | Acquired A | 75,000 | $0.00 | $0 | 75,000 | Direct |
| 05 Jun, 2026 | Robert Nelsen | Director, TenPercentOwner | Acquired A | 75,000 | $0.00 | $0 | 75,000 | Direct |
| 05 Jun, 2026 | Thomas Cahill | Director | Acquired A | 75,000 | $0.00 | $0 | 75,000 | Direct |
| 05 Jun, 2026 | Michael Aaron Kelly | Director | Acquired A | 75,000 | $0.00 | $0 | 75,000 | Direct |
| 16 Apr, 2026 | Svetlana Ni Makhni | Chief Financial Officer | Acquired A | 800,000 | $0.00 | $0 | 800,000 | Direct |
| 26 Feb, 2026 | Allan Reine | Chief Executive Officer | Acquired A | 1,300,000 | $0.00 | $0 | 1,300,000 | Direct |
| 23 Feb, 2026 | Carman Alenson | Officer | Acquired A | 140,000 | $0.00 | $0 | 140,000 | Direct |
| 23 Feb, 2026 | Ann L. Lee | Chief Technical Officer | Acquired A | 375,000 | $0.00 | $0 | 375,000 | Direct |
| 01 Aug, 2025 | Michael Aaron Kelly | Director | Disposed D | 13,510 | — | — | 0 | Direct |
| 01 Aug, 2025 | David P Schenkein | Director | Disposed D | 39,062 | — | — | 0 | Direct |
| 01 Aug, 2025 | Robert Nelsen | Director, TenPercentOwner | Disposed D | 39,062 | — | — | 0 | Direct |
| 01 Aug, 2025 | Carman Alenson | Officer | Disposed D | 16,083 | — | — | 0 | Direct |
| 01 Aug, 2025 | Kaye I Foster-Cheek | Director | Disposed D | 13,510 | — | — | 0 | Direct |
| 01 Aug, 2025 | Jeffrey D Marrazzo | Director | Disposed D | 92,000 | — | — | 0 | Direct |
| 01 Aug, 2025 | 2021 Gp, L.L.C. Gv | TenPercentOwner | Acquired P | 1,500,000 | $3.30 | $4.95Mn | 3,262,440 | Indirect |
| 01 Aug, 2025 | Ann L. Lee | Chief Technical Officer | Disposed D | 180,995 | — | — | 0 | Direct |
| 01 Aug, 2025 | Allan Reine | Chief Executive Officer | Disposed D | 850,000 | — | — | 0 | Direct |