About this page
Insider trades reported on SEC Form 4: when the people who run a company buy or sell its shares with their own money.
How to read it
- Form 4
- The form a company insider (officer, director or owner of more than 10%) must file with the SEC within two business days of buying or selling the company's shares.
- Buy (P) and Sell (S)
- Open-market purchases and sales. Gifts, option exercises and automatic tax withholding are left out because they say little about what the insider thinks.
- Value
- Shares times price, as reported on the filing.
- 10b5-1
- A trade made under a plan set up in advance. Planned sales are common and usually say less than an unplanned purchase.
- Late filing
- A Form 4 filed more than two business days after the trade.
- Vs. S&P 500
- How the stock did after the trade minus how the overall market did in the same weeks.
A real example
In January 2016, when bank stocks were falling, JPMorgan Chase CEO Jamie Dimon bought 500,000 JPMorgan shares with his own money, worth about $26 million. His Form 4 made the purchase public within days, and investors read it as a strong sign of confidence.
Explain it like I'm 13
If the coach of a team bets his own allowance that his team will win, that tells you something. A Form 4 is the note a company boss must hand in whenever he buys or sells his own company's shares, so everyone can see it.
Data from public SEC filings and congressional reports. Information, not investment advice. Check every number against the filing linked on the page.
Korro Bio, Inc. (KRRO) Insider Trading
23 open-market trades reported since Jun 17, 2026: 5 purchases worth $964K and 18 sales worth $5.46M.
By insider
| Insider | Role | Buys | Bought | Sells | Sold |
|---|---|---|---|---|---|
| Lynx1 Capital Management LP | 10% owner | 5 | $964K | 0 | $0 |
| Jean Francois Formela | Director | 0 | $0 | 10 | $5.12M |
| Oliver Dolan | President | 0 | $0 | 4 | $136K |
| Ram Aiyar | CEO | 0 | $0 | 1 | $63K |
| Jeffrey Cerio | General Counsel | 0 | $0 | 1 | $72K |
| Loic A. Vincent | Chief Scientific Officer | 0 | $0 | 1 | $37K |
| Todd Chappell | COO | 0 | $0 | 1 | $34K |
All trades
| Filed | Insider | Type | Value | Score | 3 mo. after |
|---|---|---|---|---|---|
| Oct 26 | Lynx1 Capital Management LP10% owner | ▲ BUY | $559K | 19 | |
| Oct 26 | Lynx1 Capital Management LP10% owner | ▲ BUY | $295K | 15 | |
| Oct 26 | Lynx1 Capital Management LP10% owner | ▲ BUY | $30K | 10 | |
| Sep 15 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $543K | ||
| Sep 15 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $143K | ||
| Sep 14 | Oliver DolanPresident | ▼ SELL10b5-1 | $69 | ||
| Sep 10 | Oliver DolanPresident | ▼ SELL10b5-1 | $99K | ||
| Sep 10 | Oliver DolanPresident | ▼ SELL10b5-1 | $82 | ||
| Aug 28 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $4K | ||
| Aug 21 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $399K | ||
| Aug 13 | Lynx1 Capital Management LP10% owner | ▲ BUY | $60K | 17 | |
| Aug 13 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $30K | ||
| Aug 13 | Lynx1 Capital Management LP10% owner | ▲ BUY | $19K | 7 | |
| Aug 5 | Ram AiyarCEO | ▼ SELL | $63K | ||
| Jul 7 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $1.41M | ||
| Jul 7 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $130K | ||
| Jun 24 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $1.70M | ||
| Jun 24 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $707K | ||
| Jun 24 | Jean Francois FormelaDirector | ▼ SELL10b5-1 | $55K | ||
| Jun 17 | Jeffrey CerioGeneral Counsel | ▼ SELL | $72K | ||
| Jun 17 | Loic A. VincentChief Scientific Officer | ▼ SELL | $37K | ||
| Jun 17 | Oliver DolanPresident | ▼ SELL | $37K | ||
| Jun 17 | Todd ChappellCOO | ▼ SELL | $34K |