Data spanning the past 90 days through December 12, 2025 reveals that Prime Medicine's three principal insider shareholders consist of Director Robert Nelsen (6.13Mn shares), TenPercentOwner Venture Partners X, Llc Arch (6.13Mn shares), TenPercentOwner Venture Partners Xii, Llc Arch (6.13Mn shares).
| Holder | Position | Shares | Report Date |
|---|---|---|---|
| David R. Liu | 20,240,945 | 01 Jul, 2025 | |
| Venture Partners X, Llc Arch | 6,128,297 | 01 Aug, 2025 | |
| Robert Nelsen | 6,128,297 | 01 Aug, 2025 | |
| Venture Partners Xii, Llc Arch | 6,128,297 | 01 Aug, 2025 | |
| Thomas Cahill | 5,305,679 | 26 Oct, 2022 | |
| Llc Fmr | 4,228,589 | 26 Oct, 2022 | |
| 2021 Gp, L.L.C. Gv | 3,262,440 | 05 Aug, 2025 | |
| Keith Michael Gottesdiener | 2,993,096 | 07 Jun, 2024 | |
| Allan Reine | Chief Executive Officer | 125,000 | 22 May, 2025 |
| Ann L. Lee | Chief Technical Officer | 100,000 | 22 May, 2025 |
| Richard Brudnick | Chief Business Officer | 20,000 | 22 May, 2025 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 01 Aug, 2025 | Venture Partners X, Llc Arch | Common Stock | A | 3,030,300 | $3.30 | 6,128,297 | I | P |
| 01 Aug, 2025 | Venture Partners Xii, Llc Arch | Common Stock | A | 3,030,300 | $3.30 | 6,128,297 | I | P |
| 01 Aug, 2025 | Robert Nelsen | Common Stock | A | 3,030,300 | $3.30 | 6,128,297 | I | P |
| 01 Aug, 2025 | 2021 Gp, L.L.C. Gv | Common Stock | A | 1,500,000 | $3.30 | 3,262,440 | I | P |
| 30 Jun, 2025 | David R. Liu | Common Stock | A | 21,000 | $2.52 | 20,240,945 | D | P |
| 23 Jun, 2025 | David R. Liu | Common Stock | A | 21,000 | $2.16 | 20,219,945 | D | P |
| 16 Jun, 2025 | David R. Liu | Common Stock | A | 21,000 | $1.49 | 20,198,945 | D | P |
| 11 Jun, 2025 | David R. Liu | Common Stock | A | 21,000 | $1.60 | 20,177,945 | D | P |
| 11 Jun, 2025 | David R. Liu | - | - | 20,177,945 | D | |||
| 21 May, 2025 | Ann L. Lee | Common Stock | A | 100,000 | $1.13 | 100,000 | D | P |
| 21 May, 2025 | Ann L. Lee | - | - | 100,000 | D | |||
| 21 May, 2025 | Allan Reine | Common Stock | A | 125,000 | $1.18 | 125,000 | D | P |
| 20 May, 2025 | Richard Brudnick | Common Stock | A | 20,000 | $1.19 | 20,000 | D | P |
| 20 May, 2025 | Richard Brudnick | - | - | 20,000 | D | |||
| 08 Oct, 2024 | Keith Michael Gottesdiener | Common Stock | D | 226,925 | $0.00 | 50,241 | I | G |
| 08 Oct, 2024 | Keith Michael Gottesdiener | - | - | 50,241 | I | |||
| 08 Oct, 2024 | Keith Michael Gottesdiener | - | - | 682,259 | I | |||
| 08 Oct, 2024 | Keith Michael Gottesdiener | Common Stock | A | 226,925 | $0.00 | 682,259 | I | G |
| 05 Jun, 2024 | Keith Michael Gottesdiener | Common Stock | D | 250,000 | $0.00 | 2,310,837 | D | G |
| 05 Jun, 2024 | Keith Michael Gottesdiener | - | - | 2,310,837 | D |