January 23, 2026 · Form 4 insider transaction
Hornby Zachary bought 600,000 shares of Boundless Bio, Inc. at $0.00 per share, a transaction worth N/A. The trade was recorded as grant or award and disclosed on an SEC Form 4, filed 3 days after the transaction.
The vesting commencement date is January 1, 2026. The stock option vests in 48 substantially equal monthly installments. Accordingly, 1/48th of this stock option vests on February 1, 2026, and monthly thereafter.