SION · Insider Trading
Sionna Therapeutics, Inc. Common Stock
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.
| Filed | Insider | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-09-21 | Peter Kolchinsky | Director | Sell | −20,692,866 | −$131.01M |
| 2026-09-18 | Jennifer Fitzpatrick | CLO and Head of Program Mgmt. | A | +56,265 | — |
| 2026-09-18 | Charlotte McKee | CMO and Head of R&D | A | +100,000 | — |
| 2026-09-18 | Elena Ridloff | CFO and CBO | A | +94,537 | — |
| 2026-09-18 | Michael Cloonan | President & CEO | A | +218,050 | — |
| 2026-07-09 | Peter A. Thompson | Director | Sell | −85,918 | −$3.85M |
| 2026-07-09 | ORBIMED ADVISORS LLC | Director | Sell | −171,836 | −$7.71M |
| 2026-07-07 | Jennifer Fitzpatrick | Chief Legal Officer | MIXED | — | −$384.23K |
| 2026-07-02 | Peter A. Thompson | Director | Sell | −115,844 | −$5.27M |
| 2026-07-02 | ORBIMED ADVISORS LLC | Director | Sell | −231,688 | −$10.54M |
| 2026-06-18 | Bruce Booth | Director | A | +17,340 deriv. | — |
| 2026-06-18 | Joshua Resnick | Director | A | +17,340 deriv. | — |
| 2026-06-18 | Joanne L. Viney | Director | A | +17,340 deriv. | — |
| 2026-06-18 | Peter A. Thompson | Director | A | +17,340 deriv. | — |
| 2026-06-18 | Marcella K. Ruddy | Director | A | +17,340 deriv. | — |
| 2026-06-18 | Laurie Stelzer | Director | A | +17,340 deriv. | — |
| 2026-06-18 | Harold Edward Fleming | Director | A | +17,340 deriv. | — |
| 2026-06-18 | RA CAPITAL MANAGEMENT, L.P. | Director | A | +104,040 deriv. | — |
| 2026-06-18 | Paul J Clancy | Director | A | +17,340 deriv. | — |
| 2026-05-29 | OrbiMed Capital GP VIII LLC | Director | Sell | −202 | −$8.99K |
| 2026-05-29 | Peter A. Thompson | Director | Sell | −101 | −$4.49K |
| 2026-05-11 | Peter A. Thompson | Director | Sell | −292,952 | −$13.36M |
| 2026-05-11 | ORBIMED ADVISORS LLC | Director | Sell | −585,904 | −$26.73M |
| 2026-04-21 | Peter A. Thompson | Director | Sell | −55,345 | −$2.47M |
| 2026-04-21 | ORBIMED ADVISORS LLC | Director | Sell | −110,690 | −$4.94M |
| 2026-04-16 | ORBIMED ADVISORS LLC | Director | Sell | −1,021,166 | −$45.89M |
| 2026-04-16 | Peter A. Thompson | Director | Sell | −510,583 | −$22.95M |
| 2026-03-06 | Jennifer Fitzpatrick | Chief Legal Officer | MIXED | — | −$284.39K |
| 2026-02-04 | Peter A. Thompson | Director | Sell | −30,953 | −$1.38M |
| 2026-02-04 | OrbiMed Capital GP VIII LLC | Director | Sell | −61,906 | −$2.76M |
| 2026-01-26 | James G Coulter | 10%+ Owner | Sell | −750,000 | −$30.00M |
| 2026-01-06 | Caroline Stark Beer | Chief Business Officer | A | +139,340 deriv. | — |
| 2026-01-06 | Jennifer Fitzpatrick | Chief Legal Officer | A | +103,140 deriv. | — |
| 2026-01-06 | Elena Ridloff | CFO | A | +165,440 deriv. | — |
| 2026-01-06 | Michael Cloonan | President & CEO | A | +436,100 deriv. | — |
| 2026-01-06 | Charlotte McKee | Chief Medical Officer | A | +155,700 deriv. | — |
| 2025-12-29 | Peter A. Thompson | Director | Sell | −33,356 | −$1.49M |
| 2025-12-29 | ORBIMED ADVISORS LLC | Director | Sell | −66,712 | −$2.97M |
| 2025-12-19 | OrbiMed Capital GP VIII LLC | Director | Sell | −3,750 | −$166.86K |
| 2025-12-19 | Peter A. Thompson | Director | Sell | −1,875 | −$83.43K |
| 2025-12-09 | Jennifer Fitzpatrick | Chief Legal Officer | MIXED | — | −$352.70K |
| 2025-11-26 | Peter A. Thompson | Director | Sell | −108,073 | −$4.81M |
| 2025-11-26 | OrbiMed Capital GP VIII LLC | Director | Sell | −216,146 | −$9.63M |
| 2025-11-24 | RA CAPITAL MANAGEMENT, L.P. | Director | Sell | −181,896 | −$7.20M |
| 2025-11-19 | Peter Kolchinsky | Director | Sell | −818,106 | −$33.00M |
| 2025-10-28 | RA Capital Nexus Fund III, L.P. | Director | Sell | −2,241,660 | −$88.58M |
| 2025-10-22 | Michael Cloonan | President & CEO | MIXED | — | −$3.01M |
| 2025-10-21 | Bruce Booth | Director | Sell | −88,878 | −$3.04M |
| 2025-10-20 | Bruce Booth | Director | Sell | −286,369 | −$9.25M |
| 2025-10-17 | Michael Cloonan | President & CEO | MIXED | — | −$634.18K |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| RA Capital Nexus Fund III, L.P. | Director | 6,909,249 | $26.88M |
| TPG GP A, LLC | 10%+ Owner | 6,744,962 | $26.24M |
| James G Coulter | 10%+ Owner | 6,494,962 | $25.27M |
| Atlas Venture Opportunity Fund II, L.P. | 10%+ Owner | 3,694,020 | $14.37M |
| OrbiMed Capital GP VIII LLC | Director | 2,671,721 | $10.39M |
| ORBIMED ADVISORS LLC | Director | 2,469,959 | $9.61M |
| Peter A. Thompson | Director | 2,469,959 | $9.61M |
| Bruce Booth | Director | 2,360,156 | $9.18M |
| RA CAPITAL MANAGEMENT, L.P. | Director | 661,019 | $2.57M |
| Michael Cloonan | President & CEO | 656,368 | $2.55M |
| Peter Kolchinsky | Director | 650,307 | $2.53M |
| Elena Ridloff | CFO and CBO | 85,801 | $333.77K |
| Charlotte McKee | CMO and Head of R&D | 78,415 | $305.03K |
| Jennifer Fitzpatrick | CLO and Head of Program Mgmt. | 56,265 | $218.87K |
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.
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.