KRRO · Insider Trading
Korro Bio, Inc. Common Stock
Every open-market purchase and sale reported by KRRO officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.
| Filed | Insider | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-10-26 | Lynx1 Capital Management LP | 10%+ Owner | Buy | +159,618 | +$1.77M |
| 2026-09-15 | Jean Francois Formela | Director | Sell | −48,690 | −$686.18K |
| 2026-09-14 | Oliver Dolan | Senior Vice President, Finance | Sell | −5 | −$69 |
| 2026-09-10 | Oliver Dolan | Senior Vice President, Finance | Sell | −7,353 | −$99.37K |
| 2026-08-28 | Jean Francois Formela | Director | Sell | −300 | −$4.19K |
| 2026-08-21 | Jean Francois Formela | Director | Sell | −28,468 | −$398.55K |
| 2026-08-13 | Weston Nichols | 10%+ Owner | Buy | +13,368 | +$157.62K |
| 2026-08-13 | Jean Francois Formela | Director | Sell | −2,143 | −$29.92K |
| 2026-08-05 | Ram Aiyar | President and CEO | Sell | −5,802 | −$62.92K |
| 2026-07-17 | Loic A Vincent | Chief Scientific Officer | A | +7,500 | — |
| 2026-07-17 | Todd Chappell | Chief Operating Officer | A | +7,500 | — |
| 2026-07-17 | Oliver Dolan | Senior Vice President, Finance | A | +5,500 | — |
| 2026-07-17 | Jeffrey Cerio | General Counsel | A | +6,500 | — |
| 2026-07-07 | Jean Francois Formela | Director | Sell | −110,023 | −$1.54M |
| 2026-06-24 | Jean Francois Formela | Director | Sell | −171,405 | −$2.46M |
| 2026-06-17 | Loic A Vincent | Chief Scientific Officer | Sell | −3,418 | −$37.02K |
| 2026-06-17 | Todd Chappell | Chief Operating Officer | Sell | −3,168 | −$34.31K |
| 2026-06-17 | Jeffrey Cerio | General Counsel | Sell | −6,609 | −$71.58K |
| 2026-06-17 | Oliver Dolan | Senior Vice President, Finance | Sell | −3,383 | −$36.64K |
| 2026-06-11 | Rachel Meyers | Director | A | +14,677 deriv. | — |
| 2026-06-11 | Jean Francois Formela | Director | A | +14,677 deriv. | — |
| 2026-06-11 | Ali Behbahani | Director | A | +14,677 deriv. | — |
| 2026-06-11 | Katharine Knobil | Director | A | +14,677 deriv. | — |
| 2026-06-11 | Nessan Bermingham | Director | A | +14,677 deriv. | — |
| 2026-06-11 | Timothy R Pearson | Director | A | +14,677 deriv. | — |
| 2026-06-02 | Ram Aiyar | President and CEO | Sell | −15,152 | −$196.67K |
| 2026-06-01 | Jean Francois Formela | Director | Sell | −2,860 | −$39.90K |
| 2026-05-28 | Ram Aiyar | President and CEO | A | +50,000 | +$616.50K |
| 2026-04-02 | Weston Nichols | 10%+ Owner | Buy | +1,040 | +$11.02K |
| 2026-03-12 | Rick Yang | 10%+ Owner | Buy | +207,100 | +$2.30M |
| 2026-03-12 | Anthony A. Florence Jr. | 10%+ Owner | Buy | +207,100 | +$2.30M |
| 2026-03-12 | Ali Behbahani | Director | A | +207,100 | +$2.30M |
| 2026-03-12 | Edward T Mathers | 10%+ Owner | Buy | +207,100 | +$2.30M |
| 2026-03-12 | Forest Baskett | 10%+ Owner | Buy | +207,100 | +$2.30M |
| 2026-03-12 | Paul Edward Walker | 10%+ Owner | Buy | +207,100 | +$2.30M |
| 2026-03-12 | Scott D Sandell | 10%+ Owner | Buy | +207,100 | +$2.30M |
| 2026-03-12 | NEA 17 GP, LLC | 10%+ Owner | Buy | +621,300 | +$6.90M |
| 2026-03-12 | Carmen Chang | 10%+ Owner | Buy | +207,100 | +$2.30M |
| 2026-03-12 | Mohamad Makhzoumi | 10%+ Owner | Buy | +207,100 | +$2.30M |
| 2026-02-03 | Jeffrey Cerio | General Counsel | A | +23,000 deriv. | — |
| 2026-02-03 | Todd Chappell | Chief Operating Officer | A | +38,000 deriv. | — |
| 2026-02-03 | Oliver Dolan | Senior Vice President, Finance | A | +15,000 deriv. | — |
| 2026-02-03 | Loic A Vincent | Chief Scientific Officer | A | +35,000 deriv. | — |
| 2026-02-03 | Ram Aiyar | President and CEO | A | +40,000 | — |
| 2025-12-16 | Oliver Dolan | Senior Vice President, Finance | A | +21,482 | — |
| 2025-12-16 | Jeffrey Cerio | General Counsel | A | +41,902 | — |
| 2025-12-16 | Loic A Vincent | Chief Scientific Officer | A | +21,715 | — |
| 2025-12-16 | Todd Chappell | Chief Operating Officer | A | +20,132 | — |
| 2025-06-12 | Nessan Bermingham | Director | A | +6,010 deriv. | — |
| 2025-06-12 | Jean Francois Formela | Director | A | +6,010 deriv. | — |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| Weston Nichols | 10%+ Owner | 1,544,980 | $18.57M |
| Scott D Sandell | 10%+ Owner | 1,297,893 | $15.60M |
| Rick Yang | 10%+ Owner | 1,297,893 | $15.60M |
| NEA 17 GP, LLC | 10%+ Owner | 1,297,893 | $15.60M |
| Carmen Chang | 10%+ Owner | 1,297,893 | $15.60M |
| Mohamad Makhzoumi | 10%+ Owner | 1,297,893 | $15.60M |
| Ali Behbahani | Director | 1,297,893 | $15.60M |
| Anthony A. Florence Jr. | 10%+ Owner | 1,297,893 | $15.60M |
| Paul Edward Walker | 10%+ Owner | 1,297,893 | $15.60M |
| Edward T Mathers | 10%+ Owner | 1,297,893 | $15.60M |
| Forest Baskett | 10%+ Owner | 1,297,893 | $15.60M |
| Jean Francois Formela | Director | 132,650 | $1.59M |
| Ram Aiyar | President and CEO | 73,659 | $885.38K |
| Jeffrey Cerio | General Counsel | 41,793 | $502.35K |
| Loic A Vincent | Chief Scientific Officer | 25,797 | $310.08K |
| Todd Chappell | Chief Operating Officer | 24,464 | $294.06K |
| Oliver Dolan | Senior Vice President, Finance | 16,241 | $195.22K |
| Vineet Agarwal | Chief Financial Officer | 800 | $9.62K |
Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.
Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.
Full filing history and per-insider positions are on the KRRO quote page; the site-wide leaderboard is on the insider transactions hub.
Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.