BillionToOne CTO David Tsao Exercises Options and Sells Shares Under 10b5-1 Plan

David Tsao, Chief Technology Officer of BillionToOne, Inc., executed significant stock transactions on June 15, 2026, pursuant to a Rule 10b5-1 trading plan adopted on March 6, 2026. Tsao exercised 20,000 stock options at $2.80 per share, acquiring 20,000 shares of Class A Common Stock. Concurrently, he sold 21,000 shares through multiple transactions at prices ranging from $98.16 to $104.61 per share, resulting in net sales of approximately 1,000 shares. The transactions were executed under a pre-arranged trading plan, which helps insiders avoid allegations of trading on material non-public information. Following these transactions, Tsao's direct holdings decreased to 1,000 shares, while he retains 620,000 exercisable stock options expiring in 2031.