Booth Bruce sold SION

October 16, 2025 · Form 4 insider transaction

Booth Bruce sold 45,117 shares of Sionna Therapeutics, Inc. at $31.69 per share, a transaction worth $1.43M. The trade was recorded as open-market sale under a pre-scheduled Rule 10b5-1 plan and disclosed on an SEC Form 4, filed 4 days after the transaction.

Direction
Disposed (sell-side)
Shares
45,117
Price
$31.69
Total value
$1.43M
RoleDirector
SecurityCommon Stock
Transaction codeS: Open-market sale
Transaction dateOctober 16, 2025
Filing dateOctober 20, 2025
Shares owned after2,565,472
OwnershipIndirect
10b5-1 planYes
AmendedNo

Footnotes

This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by Atlas Venture Fund XI, L.P. on February 25, 2025.; The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $31.21 to $32.205 inclusive.; These shares are held directly by Atlas Venture Fund XI, L.P. ("AVF XI "). The general partner of AVF XI is Atlas Venture Associates XI, L.P. ("AVA XI LP"). Atlas Venture Associates XI, LLC ("AVA XI LLC") is the general partner of AVA XI LP. The Reporting Person is a member of AVA XI LLC and disclaims beneficial ownership of such securities held by AVF XI, except to the extent of his pecuniary interest therein, if any.

View the original Form 4 on SEC EDGAR