BillionToOne (BLLN) GC Thomas Lynch Exercises Options, Sells Shares

What Happened

• Thomas P. Lynch, General Counsel, Chief Compliance Officer and Secretary of BillionToOne (BLLN), exercised 20,000 stock options on 2026-09-08 (four option tranches: 11,042; 3,969; 1,663; 3,326). He paid about $272,200 in aggregate exercise costs (various strike prices $8.65–$30.78).
• On the same day Lynch sold 20,000 shares in open-market transactions for approximately $2.0 million (weighted-average prices around $99.67–$101.65 across different lots). The filings also report the exercised option shares as disposed (same-day sale/cashless pattern). This is an option exercise (M) plus sales (S), not a grant/award.

Key Details

• Transaction date: September 8, 2026; Form 4 filed September 10, 2026 (timely filing).
• Options exercised: 20,000 shares; aggregate exercise cost ≈ $272,200 (strikes $8.65, $11.55, $17.12, $30.78).
• Shares sold: 20,000 open-market shares; gross proceeds ≈ $2.0M (weighted-average prices and price ranges disclosed in footnotes).
• Net cash (approx): open-market proceeds ~$2.0M minus exercise cost ~$272k ≈ $1.73M (simple difference; does not account for fees/taxes).
• Notable footnotes: transactions were executed under a Rule 10b5-1 trading plan adopted June 8, 2026 (F1); options were fully vested and exercisable (F12); multiple sales reported as weighted-average prices with disclosed price ranges (F2–F11).
• Shares owned after transaction: not provided in the excerpt.

Context

• This is a common pattern where an insider exercises vested options and sells the resulting shares (often called a cashless exercise or same-day sale). The exercise prices were substantially lower than the resale prices, so the transactions realized built-in gains on those option grants.
• Transactions were reported under a pre-established 10b5-1 plan, which indicates the trades were scheduled under an automated plan rather than ad hoc trading decisions.