SION (Sionna Therapeutics, Inc. Common Stock)

Insider Trading Activity

Every open-market purchase and sale reported by SION officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.

Form 4 Filings
50
most recent
Open-Market Buys
0
code P
Sales
29
code S
Reporting Insiders
12
current holders
SION — Recent Form 4 Transactions (latest 2026-07-09)
FiledInsiderRole TypeSharesValue
2026-07-09 Peter A. Thompson Director Sell
2026-07-09 ORBIMED ADVISORS LLC Director Sell
2026-07-07 Jennifer Fitzpatrick Chief Legal Officer MIXED
2026-07-02 Peter A. Thompson Director Sell
2026-07-02 ORBIMED ADVISORS LLC Director Sell
2026-06-18 Bruce Booth Director A
2026-06-18 Joshua Resnick Director A
2026-06-18 Joanne L. Viney Director A
2026-06-18 Peter A. Thompson Director A
2026-06-18 Marcella K. Ruddy Director A
2026-06-18 Laurie Stelzer Director A
2026-06-18 Harold Edward Fleming Director A
2026-06-18 RA CAPITAL MANAGEMENT, L.P. Director A
2026-06-18 Paul J Clancy Director A
2026-05-29 OrbiMed Capital GP VIII LLC Director Sell
2026-05-29 Peter A. Thompson Director Sell
2026-05-11 Peter A. Thompson Director Sell
2026-05-11 ORBIMED ADVISORS LLC Director Sell
2026-04-21 Peter A. Thompson Director Sell
2026-04-21 ORBIMED ADVISORS LLC Director Sell
2026-04-16 ORBIMED ADVISORS LLC Director Sell
2026-04-16 Peter A. Thompson Director Sell
2026-03-06 Jennifer Fitzpatrick Chief Legal Officer MIXED
2026-02-04 Peter A. Thompson Director Sell
2026-02-04 OrbiMed Capital GP VIII LLC Director Sell
2026-01-26 JAMES G COULTER 10%+ Owner Sell
2026-01-06 Caroline Stark Beer Chief Business Officer A
2026-01-06 Jennifer Fitzpatrick Chief Legal Officer A
2026-01-06 Elena Ridloff CFO A
2026-01-06 Michael Cloonan President & CEO A
2026-01-06 Charlotte McKee Chief Medical Officer A
2025-12-29 Peter A. Thompson Director Sell
2025-12-29 ORBIMED ADVISORS LLC Director Sell
2025-12-19 OrbiMed Capital GP VIII LLC Director Sell
2025-12-19 Peter A. Thompson Director Sell
2025-12-09 Jennifer Fitzpatrick Chief Legal Officer MIXED
2025-11-26 Peter A. Thompson Director Sell
2025-11-26 OrbiMed Capital GP VIII LLC Director Sell
2025-11-24 RA CAPITAL MANAGEMENT, L.P. Director Sell
2025-11-19 Peter Kolchinsky Director Sell
2025-10-28 RA Capital Nexus Fund III, L.P. Director Sell
2025-10-22 Michael Cloonan President & CEO MIXED
2025-10-21 Bruce Booth Director Sell
2025-10-20 Bruce Booth Director Sell
2025-10-17 Michael Cloonan President & CEO MIXED
2025-10-15 Bruce Booth Director Sell
2025-10-07 Bruce Booth Director Sell
2025-10-03 Caroline Stark Beer Chief Business Officer A
2025-10-01 Bruce Booth Director Sell
2025-09-30 Michael Cloonan President & CEO MIXED
SION — Current Insider Holders
InsiderRole Shares HeldValue
Director 6,909,249
Director 6,899,079
10%+ Owner 6,744,962
10%+ Owner 6,494,962
10%+ Owner 3,694,020
Director 2,671,721
Director 2,469,959
Director 2,469,959
Director 2,360,156
Director 661,019
President & CEO 547,343
CFO 47,368
How to read Form 4 activity

Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.

Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.

Full filing history and per-insider positions are on the SION quote page; the site-wide leaderboard is on the insider transactions hub.