KRRO insider buying and SEC filings, explained
Korro Bio, Inc. · CIK 1703647
Tracked: Forms 3/4/5, 8-K, NT · All filings on sec.gov
Insider activity in the last 12 months
Bought
$964K
Insiders who bought
1
Sold (not marked 10b5-1)
$439K
Planned sales (10b5-1)
$5.3M
Insider purchases and sales, last 12 months
| Traded | Type | What was filed | Source |
|---|---|---|---|
| Oct 22–26, 2026 | Purchase (code P) | Weston Nichols (10% owner) bought 79,809 shares indirectly between Oct 22 and Oct 26 at about $11.09 ($885K), reported as a purchase (code P). Indirect holdings up 5% to 1,624,789 shares. Not marked as a 10b5-1 plan trade. Filed jointly with 1 other reporting owner. | SEC filing Filed Oct 26, 2026, 6:37 PM ET |
| Sep 11–14, 2026 | Planned (10b5-1) | Jean Francois Formela (Director) sold 48,690 shares indirectly between Sep 11 and Sep 14 at about $14.09 ($686K), marked as a 10b5-1 plan trade. Indirect holdings down 27% to 132,650 shares. | SEC filing Filed Sep 15, 2026 |
| Sep 11, 2026 | Planned (10b5-1) | Oliver Dolan (Senior Vice President, Finance) sold 5 shares at about $13.72 ($69), marked as a 10b5-1 plan trade. Holdings down <1% to 16,241 shares. | SEC filing Filed Sep 14, 2026 |
| Sep 8–9, 2026 | Planned (10b5-1) | Oliver Dolan (Senior Vice President, Finance) sold 7,353 shares between Sep 8 and Sep 9 at about $13.51 ($99K), marked as a 10b5-1 plan trade. Holdings down 31% to 16,246 shares. | SEC filing Filed Sep 10, 2026 |
| Aug 26, 2026 | Planned (10b5-1) | Jean Francois Formela (Director) sold 300 shares indirectly at about $13.96 ($4K), marked as a 10b5-1 plan trade. Indirect holdings down <1% to 141,002 shares. | SEC filing Filed Aug 28, 2026 |
| Aug 19, 2026 | Planned (10b5-1) | Jean Francois Formela (Director) sold 28,468 shares indirectly at about $14.00 ($399K), marked as a 10b5-1 plan trade. Indirect holdings down 17% to 141,053 shares. | SEC filing Filed Aug 21, 2026 |
| Aug 11, 2026 | Planned (10b5-1) | Jean Francois Formela (Director) sold 2,143 shares indirectly at about $13.96 ($30K), marked as a 10b5-1 plan trade. Indirect holdings down 1% to 145,937 shares. | SEC filing Filed Aug 13, 2026 |
| Aug 6–10, 2026 | Purchase (code P) | Weston Nichols (10% owner) bought 6,684 shares indirectly between Aug 6 and Aug 10 at about $11.79 ($79K), reported as a purchase (code P). Indirect holdings up <1% to 1,544,980 shares. Not marked as a 10b5-1 plan trade. Filed jointly with 1 other reporting owner. | SEC filing Filed Aug 13, 2026 |
| Aug 4, 2026 | Sale | Ram Aiyar (CEO and Director) sold 5,802 shares at about $10.84 ($63K). Holdings down 8% to 69,046 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Aug 5, 2026 |
| Jul 2–6, 2026 | Planned (10b5-1) | Jean Francois Formela (Director) sold 110,023 shares indirectly between Jul 2 and Jul 6 at about $14.02 ($1.5M), marked as a 10b5-1 plan trade. Indirect holdings down 43% to 146,305 shares. | SEC filing Filed Jul 7, 2026 |
| Jun 22–24, 2026 | Planned (10b5-1) | Jean Francois Formela (Director) sold 171,405 shares indirectly between Jun 22 and Jun 24 at about $14.34 ($2.5M), marked as a 10b5-1 plan trade. Indirect holdings down 50% to 169,556 shares. | SEC filing Filed Jun 24, 2026 |
| Jun 16, 2026 | Sale | Todd Chappell (President / COO) sold 3,168 shares at about $10.83 ($34K). Holdings down 16% to 16,964 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 17, 2026 |
| Jun 16, 2026 | Sale | Loic A Vincent (Chief Scientific Officer) sold 3,418 shares at about $10.83 ($37K). Holdings down 16% to 18,297 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 17, 2026 |
| Jun 16, 2026 | Sale | Jeffrey Cerio (General Counsel) sold 6,609 shares at about $10.83 ($72K). Holdings down 16% to 35,293 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 17, 2026 |
| Jun 16, 2026 | Sale | Oliver Dolan (Senior Vice President, Finance) sold 3,383 shares at about $10.83 ($37K). Holdings down 16% to 18,099 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 17, 2026 |
| May 29, 2026 | Sale | Ram Aiyar (CEO and Director) sold 15,152 shares at about $12.98 ($197K). Holdings down 17% to 74,848 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 2, 2026 |
| May 28, 2026 | Planned (10b5-1) | Jean Francois Formela (Director) sold 2,860 shares indirectly at $13.95 ($40K), marked as a 10b5-1 plan trade. Indirect holdings down 1% to 194,655 shares. | SEC filing Filed Jun 1, 2026 |
| Mar 31, 2026 | Purchase (code P) | Weston Nichols (10% owner) bought 520 shares indirectly at $10.60 ($6K), reported as a purchase (code P). Indirect holdings up <1% to 1,538,296 shares. Not marked as a 10b5-1 plan trade. Filed jointly with 1 other reporting owner. | SEC filing Filed Apr 2, 2026 |
| Mar 10, 2026 | Other purchase | Rick Yang (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes indirectly at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
| Mar 10, 2026 | Other purchase | Scott D. Sandell (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes indirectly at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
| Mar 10, 2026 | Other purchase | New Enterprise Associates 17, L.P. (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. Filed jointly with 2 other reporting owners. | SEC filing Filed Mar 12, 2026 |
| Mar 10, 2026 | Other purchase | Carmen Chang (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes indirectly at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
| Mar 10, 2026 | Other purchase | Forest Baskett (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes indirectly at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
| Mar 10, 2026 | Other purchase | Edward T Mathers (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes indirectly at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
| Mar 10, 2026 | Other purchase | Paul Edward Walker (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes indirectly at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
| Mar 10, 2026 | Other purchase | Mohamad Makhzoumi (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes indirectly at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
| Mar 10, 2026 | Other purchase | Anthony A. Florence Jr. (10% owner) bought 450,045 Pre-Funded Warrants in 2 share classes indirectly at $11.11 ($5.0M) in a private placement. New position of 242,945 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
21 routine transactions (such as grants, option exercises or tax withholding) are not listed.
Cluster buys
No cluster buys in the last 12 months.
Red flags
No red flags in the last 12 months.
Key events
No key events in the last 12 months.
8-K filings, last 12 months
No 8-K filings in the last 12 months.
Red flags are objective triggers only: the item or form filed, never an opinion.
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