PRME insider buying – Prime Medicine, Inc.
12 insider purchases since 2016 worth $55.8M by 9 different insiders. Last 12 months: 0 purchases, $0. Most recent filing: 2025-08-05.
Small company Public float $239M (latest 10-K, SEC). Share prices of small companies usually swing much more than those of large ones, in both directions, and are easier to move with little trading.
Same time range as the chart above - each mark sits under the week of the trade. Circles = purchases (height = price paid, size = amount), red triangles = open-market sales of $50k+. Prices as reported, not adjusted for later stock splits.
Purchases are open-market buys (SEC Form 4, code "P") - insiders paying with their own money. Sales are open-market sales (code "S") of $50,000 or more; many sales are pre-planned (Rule 10b5-1) or made for taxes and diversification. Each row links to the original filing.
Bought, sold, still holding?
| Insider | Bought | First / last buy | Sold since 2016 | Holds now* | Status |
|---|---|---|---|---|---|
| ARCH Venture Partners X, L.P. 10% Owner | $20.0M 1× · 3,200,000 sh | 2024-02-15 2024-02-15 | – | 15,456,594 shares as of 2024-02-20 | Holds - never sold |
| NELSEN ROBERT Director | $13.6M 1× · 800,000 sh | 2022-10-24 2022-10-24 | – | 18,502,974 shares as of 2025-08-01 | Holds - never sold |
| GILLIS STEVEN 10% Owner | $10.0M 1× · 3,030,300 sh | 2025-08-01 2025-08-01 | – | 18,486,894 shares as of 2025-08-01 | Holds - never sold |
| Cahill Thomas Director | $6.8M 1× · 400,000 sh | 2022-10-24 2022-10-24 | – | 5,305,679 shares as of 2022-10-26 | Holds - never sold |
| Alphabet Inc. 10% Owner | $5.0M 1× · 1,500,000 sh | 2025-08-01 2025-08-01 | 3× · $3.4M last 2023-06-15 | 3,262,440 shares as of 2025-08-05 | Holds (sold earlier) |
| Liu David R. 10% Owner | $163,170 4× · 84,000 sh | 2025-06-11 2025-06-30 | – | 20,240,945 shares as of 2025-07-01 | Holds - never sold |
| Reine Allan CEO | $147,500 1× · 125,000 sh | 2025-05-21 2025-05-21 | – | 125,000 shares as of 2025-05-22 | Holds - never sold |
| LEE ANN L. Officer | $113,000 1× · 100,000 sh | 2025-05-21 2025-05-21 | – | 100,000 shares as of 2025-05-22 | Holds - never sold |
| Brudnick Richard Officer | $23,800 1× · 20,000 sh | 2025-05-20 2025-05-20 | – | 20,000 shares as of 2025-05-22 | Holds - never sold |
* Shares held after the insider's most recent SEC filing for this company (all share classes, direct and indirect). If an insider stops filing, later changes are not known.
Insider buying and selling by year
| Year | Purchases | Bought | Buyers | Sales | Sold |
|---|---|---|---|---|---|
| 2025 | 9 | $15.4M | 6 | – | – |
| 2024 | 1 | $20.0M | 1 | – | – |
| 2023 | 0 | – | – | 15 | $20.0M |
| 2022 | 2 | $20.4M | 2 | – | – |
Insider purchases
| Filed | Insider | Role | Shares | Avg price | Value | Holdings | Filing |
|---|---|---|---|---|---|---|---|
| 2025-08-05 | Alphabet Inc. | 10% Owner | 1,500,000 | $3.30 | $5.0M | +85.1% | SEC |
| 2025-08-01 | GILLIS STEVEN | 10% Owner | 3,030,300 | $3.30 | $10.0M | +94.7% | SEC |
| 2025-07-01 | Liu David R. | 10% Owner | 21,000 | $2.52 | $52,920 | +0.1% | SEC |
| 2025-06-23 | Liu David R. | 10% Owner | 21,000 | $2.16 | $45,360 | +0.1% | SEC |
| 2025-06-16 | Liu David R. | 10% Owner | 21,000 | $1.49 | $31,290 | +0.1% | SEC |
| 2025-06-12 | Liu David R. | 10% Owner | 21,000 | $1.60 | $33,600 | +0.1% | SEC |
| 2025-05-22 | Reine Allan | CEO | 125,000 | $1.18 | $147,500 | SEC | |
| 2025-05-22 | LEE ANN L. | Officer | 100,000 | $1.13 | $113,000 | SEC | |
| 2025-05-22 | Brudnick Richard | Officer | 20,000 | $1.19 | $23,800 | SEC | |
| 2024-02-20 | ARCH Venture Partners X, L.P. | 10% Owner | 3,200,000 | $6.25 | $20.0M | SEC | |
| 2022-10-26 | NELSEN ROBERT | Director | 800,000 | $17.00 | $13.6M | +15.0% | SEC |
| 2022-10-26 | Cahill Thomas | Director | 400,000 | $17.00 | $6.8M | +8.2% | SEC |
Insider sales
| Filed | Insider | Role | Shares | Avg price | Value | Type | Filing |
|---|---|---|---|---|---|---|---|
| 2023-06-22 | GV 2021 GP, L.P. | 10% Owner | 56,408 | $15.03 | $847,794 | Pre-planned (10b5-1) | SEC |
| 2023-06-20 | Alphabet Inc. | 10% Owner | 73,191 | $14.93 | $1.1M | Pre-planned (10b5-1) | SEC |
| 2023-06-15 | GV 2021 GP, L.P. | 10% Owner | 57,060 | $15.00 | $855,788 | Pre-planned (10b5-1) | SEC |
| 2023-06-13 | GV 2019 GP, L.L.C. | 10% Owner | 31,703 | $14.73 | $467,075 | Pre-planned (10b5-1) | SEC |
| 2023-06-09 | GV 2021 GP, L.P. | 10% Owner | 20,000 | $16.62 | $332,500 | Pre-planned (10b5-1) | SEC |
| 2023-06-07 | GV 2021 GP, L.P. | 10% Owner | 52,409 | $16.88 | $884,822 | Pre-planned (10b5-1) | SEC |
| 2023-06-02 | GV 2021 GP, L.L.C. | 10% Owner | 61,856 | $14.16 | $876,179 | Pre-planned (10b5-1) | SEC |
| 2023-05-31 | GV 2019 GP, L.L.C. | 10% Owner | 29,407 | $13.70 | $402,876 | Pre-planned (10b5-1) | SEC |
| 2023-05-26 | Alphabet Inc. | 10% Owner | 31,061 | $13.45 | $417,808 | Pre-planned (10b5-1) | SEC |
| 2023-05-24 | Alphabet Inc. | 10% Owner | 131,861 | $14.33 | $1.9M | Pre-planned (10b5-1) | SEC |
| 2023-05-22 | GV 2021 GP, L.P. | 10% Owner | 90,310 | $13.63 | $1.2M | Pre-planned (10b5-1) | SEC |
| 2023-05-18 | GV 2021, L.P. | 10% Owner | 65,649 | $12.63 | $829,221 | Pre-planned (10b5-1) | SEC |
| 2023-05-16 | GV 2019 GP, L.L.C. | 10% Owner | 185,242 | $12.74 | $2.4M | Pre-planned (10b5-1) | SEC |
| 2023-05-12 | GV 2019, L.P. | 10% Owner | 114,023 | $13.82 | $1.6M | Pre-planned (10b5-1) | SEC |
| 2023-05-10 | GV 2021 GP, L.P. | 10% Owner | 422,010 | $14.09 | $5.9M | Pre-planned (10b5-1) | SEC |
Compiled automatically from public SEC filings. Not investment advice. Get every new insider purchase in the daily report.
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