Sionna Therapeutics, Inc. SION
CIK 0002036042
Form 3 statements with an event date from Sep 1, 2023 to Sep 23, 2026.
Where insider ownership starts.
Form 3 is an initial ownership statement filed when someone becomes a reporting insider. These holdings do not mean they bought shares that day.
| Holdings date | Insider | Initial holdings | |
|---|---|---|---|
| 2025-10-01 | Beer Caroline Stark Chief Business Officer | No securities reported | ▾ |
| 2025-04-01 | Fitzpatrick Jennifer Chief Legal Officer | 2 derivative holdings | ▾ |
| 2025-02-06 | COULTER JAMES G · WINKELRIED JON · TPG GP A, LLC 10% owner / 10% owner / 10% owner | 684.41K shares · 4 derivative holdings | ▾ |
| 2025-02-06 | RA Capital Healthcare Fund LP · RA CAPITAL MANAGEMENT, L.P. · Kolchinsky Peter · Shah Rajeev M. · RA Capital Nexus Fund, L.P. · RA Capital Nexus Fund III, L.P. Director · 10% owner / Director · 10% owner / Director · 10% owner / Director · 10% owner / Director / Director | 3 stock holdings · 10 derivative holdings | ▾ |
| 2025-02-06 | Stelzer Laurie Director | 1 derivative holding | ▾ |
| 2025-02-06 | McKee Charlotte Chief Medical Officer | 28.41K shares · 2 derivative holdings | ▾ |
| 2025-02-06 | Iancovici Lucian Director | No securities reported | ▾ |
| 2025-02-06 | Ruddy Marcella K. Director | No securities reported | ▾ |
| 2025-02-06 | Atlas Venture Fund XI, L.P. · Atlas Venture Associates XI, LLC · Atlas Venture Associates XI, L.P. · Atlas Venture Opportunity Fund II, L.P. · Atlas Venture Associates Opportunity II, LLC · Atlas Venture Associates Opportunity II, LP 10% owner / 10% owner / 10% owner / 10% owner / 10% owner / 10% owner | 5 derivative holdings | ▾ |
| 2025-02-06 | Cloonan Michael President & CEO · Director | 547.34K shares · 2 derivative holdings | ▾ |
| 2025-02-06 | Thompson Peter A. Director | 2 derivative holdings | ▾ |
| 2025-02-06 | Viney Joanne L. Director | No securities reported | ▾ |
| 2025-02-06 | Resnick Joshua Director | No securities reported | ▾ |
| 2025-02-06 | Fleming Harold Edward Director | No securities reported | ▾ |
| 2025-02-06 | Clancy Paul J Director | 2 derivative holdings | ▾ |
| 2025-02-06 | Ridloff Elena CFO & Head of Corp. Dev. | 123.53K shares · 3 derivative holdings | ▾ |
| 2025-02-06 | Booth Bruce Director | 5 derivative holdings | ▾ |
| 2025-02-06 | ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director / Director | 2 derivative holdings | ▾ |
Showing 18 / 18 statements in 2025. The complete set is available through the API.
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