David Tsao sold $417k of BLLN
Chief Technology Officer at BillionToOne, Inc.. 3,333 shares at an average of $125.00, traded Sep 24, 2026, filed Sep 28, 2026.
Score components
- +15RoleOfficer
- +16Trade size$417k at market
- +20Share of holdings soldSold 77% of holdings
- +15Cluster4 insiders selling within 14 days
- -15Exercise and sellShares came from an option exercise in the same filing
- -2010b5-1 planPre-scheduled under a 10b5-1 plan
What happened after comparable sells
Same side and tier, against the S&P 500, at 1, 3 and 6 months. Shown to Pro users; the whole table is on the backtest page.
Price around the trade, and since
From a quarter before the trade to today. The arrow is the trade, the circle the day the filing reached EDGAR, which is the first day anyone outside could act; the dotted line is the S&P 500 rebased to that day's close.
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value; the dashed line is the close on the filing day, the dotted line SPY rebased to it.Charts by TradingView Lightweight Charts™
Rows in this filing
Every transaction in Form 4 0002087127-26-000013, as filed. Open on EDGAR
| Date | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|
| Sep 24, 2026 | MOption exercise Class A Common Stock10b5-1 | +3,333 | $2.80 | $9,332 | 4,333 | 15 d ago |
| Sep 24, 2026 | SOpen-market sale Class A Common Stock10b5-1 | -3,333 | $125.00 | $417k | 1,000 | 15 d ago |
| Sep 24, 2026 | MOption exercise Stock Option (right to buy)derivative10b5-1 | -3,333 | $2.80 | $9,332 | 556,667 | 15 d ago |
Related signals
Other insiders at BillionToOne, Inc. and this insider’s other filings.
| Score | Company | Insider | Value | Holdings | Filed |
|---|---|---|---|---|---|
| 29Weak | BillionToOne, Inc. | John Roderick ten Bosch SVP of Laboratory Operations | $298k 2,834 shares | -13% | |
| 40Moderate | BillionToOne, Inc. | David Tsao Chief Technology Officer | $2.2M 20,000 shares | -95% | |
| 50Moderate | BillionToOne, Inc. | Oguzhan Atay Chairman and CEO | $1.3M 10,999 shares | -132% | |
| 21Weak | BillionToOne, Inc. | John Roderick ten Bosch SVP of Laboratory Operations | $170k 1,416 shares | -6% | |
| 21Weak | BillionToOne, Inc. | John Roderick ten Bosch SVP of Laboratory Operations | $151k 1,416 shares | -6% | |
| 40Moderate | BillionToOne, Inc. | Thomas P. Lynch See Remarks | $3.9M 35,112 shares | -98% | |
| 50Moderate | BillionToOne, Inc. | Oguzhan Atay Chairman and CEO | $3.0M 30,331 shares | -121% | |
| 21Weak | BillionToOne, Inc. | John Roderick ten Bosch SVP of Laboratory Operations | $138k 1,416 shares | -5% | |
| 40Moderate | BillionToOne, Inc. | David Tsao Chief Technology Officer | $2.0M 20,000 shares | -95% | |
| 40Moderate | BillionToOne, Inc. | Thomas P. Lynch See Remarks | $2.0M 20,000 shares | -97% |
Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.