October 14, 2025 · Form 4 insider transaction
Booth Bruce sold 105 shares of Sionna Therapeutics, Inc. at $29.95 per share, a transaction worth $3.1K. The trade was recorded as open-market sale under a pre-scheduled Rule 10b5-1 plan and disclosed on an SEC Form 4, filed 1 day after the transaction.
This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Opportunity Fund II, L.P. on February 25, 2025.; These shares are held directly by Atlas Venture Opportunity Fund II, L.P. ("AVOF II"). The general partner of AVOF II is Atlas Venture Associates Opportunity II, L.P. ("AVAO II LP"). Atlas Venture Associates Opportunity II, LLC ("AVAO II LLC") is the general partner of AVAO II LP. The Reporting Person is a member of AVAO II LLC and disclaims beneficial ownership of such securities held by AVOF II, except to the extent of his pecuniary interest therein, if any.