June 23, 2026 · Form 4 insider transaction
THOMAS FRANK E bought 10,000 shares of Spero Therapeutics, 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 2 days after the transaction.
Consists of restricted stock units ("RSUs"). Each RSU represents the right to receive one share of common stock upon vesting. The RSUs vest on June 23, 2027, subject to the Reporting Person's continued service through the applicable vesting date.