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Michael Cloonan owns 1.69% of Sionna Therapeutics

765,393 shares as of the September 17, 2026 filing, worth $2.8M at the latest close.

SION · $167M market cap
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Free.
The stake
1.69%
worth $2.8M at the latest close
Stake rank
#2,348
by dollar value of the stake
Last sale
None
no sales since 2016
Last buy
None
no purchases since 2016

Michael Cloonan owns 1.69% of Sionna Therapeutics, Inc.: 765,393 of 45,212,399 shares, worth about $2.8M at the 2026-10-26 close. The stake has moved from 1.24% in 2025 to 1.69% on 2026-09-17.

How the stake is held

as of the Sep 17, 2026 filing
SHARES
OF THE STAKE
COMMON STOCK · stated Sep 17, 2026 · Form 4 ↗
HELD DIRECTLY
765,393
100.0%
THE STAKE
765,393
1.69%