INSM (Insmed, Inc.)

Insider Trading Activity

Every open-market purchase and sale reported by INSM 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
19
code S
Reporting Insiders
25
current holders
INSM — Recent Form 4 Transactions (latest 2026-08-07)
FiledInsiderRole TypeSharesValue
2026-08-07 Martina M.D. Flammer Chief Medical Officer MIXED
2026-07-24 William Lewis Chair and CEO MIXED
2026-07-10 William Lewis Chair and CEO MIXED
2026-07-08 Martina M.D. Flammer Chief Medical Officer MIXED
2026-06-26 William Lewis Chair and CEO MIXED
2026-06-24 Michael Alexander Smith Chief Legal Officer Sell
2026-06-24 Samuele Butera SVP, GM, Global Respiratory A
2026-06-10 William Lewis Chair and CEO Sell
2026-06-05 Martina M.D. Flammer Chief Medical Officer Sell
2026-06-05 William Lewis Chair and CEO Sell
2026-06-05 Michael Alexander Smith Chief Legal Officer Sell
2026-06-05 Sara Bonstein Chief Financial Officer Sell
2026-06-05 Roger Adsett Chief Operating Officer Sell
2026-05-22 Michael Alexander Smith Chief Legal Officer Sell
2026-05-20 William Lewis Chair and CEO MIXED
2026-05-15 William Lewis Chair and CEO Sell
2026-05-15 LEO LEE Director A
2026-05-15 Clarissa Desjardins Director A
2026-05-15 David R Brennan Director A
2026-05-15 MELVIN MD SHAROKY Director A
2026-05-15 Michael Alexander Smith Chief Legal Officer Sell
2026-05-15 Martina M.D. Flammer Chief Medical Officer Sell
2026-05-15 ELIZABETH M ANDERSON Director A
2026-05-15 Roger Adsett Chief Operating Officer Sell
2026-05-15 CAROL SCHAFER Director A
2026-05-15 Sara Bonstein Chief Financial Officer Sell
2026-05-13 Martina M.D. Flammer Chief Medical Officer MIXED
2026-05-06 William Lewis Chair and CEO MIXED
2026-04-17 William Lewis Chair and CEO MIXED
2026-04-08 William Lewis Chair and CEO MIXED
2026-04-03 Roger Adsett Chief Operating Officer MIXED
2026-03-31 Michael Alexander Smith Chief Legal Officer MIXED
2026-03-20 William Lewis Chair and CEO MIXED
2026-03-05 MELVIN MD SHAROKY Director G
2026-03-05 William Lewis Chair and CEO MIXED
2026-02-27 MELVIN MD SHAROKY Director G
2026-02-25 David R Brennan Director G
2026-02-25 Michael Alexander Smith Chief Legal Officer MIXED
2026-02-23 William Lewis Chair and CEO MIXED
2026-02-11 William Lewis Chair and CEO MIXED
2026-02-11 DAVID W J MCGIRR Director G
2026-02-06 Martina M.D. Flammer Chief Medical Officer Sell
2026-02-04 Martina M.D. Flammer Chief Medical Officer MIXED
2026-02-04 Michael Alexander Smith Chief Legal Officer Sell
2026-02-04 William Lewis Chair and CEO Sell
2026-02-04 Sara Bonstein Chief Financial Officer Sell
2026-02-04 Roger Adsett Chief Operating Officer Sell
2026-01-22 William Lewis Chair and CEO MIXED
2026-01-13 Martina M.D. Flammer Chief Medical Officer Sell
2026-01-13 William Lewis Chair and CEO MIXED
INSM — Current Insider Holders
InsiderRole Shares HeldValue
Chair and CEO 503,682
Director 320,802
Director 252,928
President, CEO and Chairman 182,668
Chief Legal Officer 149,985
Chief Commercial Officer 140,935
Director 124,238
Chief Operating Officer 98,603
Director 97,723
Chief Medical Officer 78,764
Director 73,337
Director 71,288
Director 69,495
Chief Financial Officer 69,082
Director 66,622
Director 62,197
Director 62,034
Executive VP & CFO 59,729
Director 57,971
Chief Compliance Officer 52,553
President Follow-on Biologics 47,716
SVP, Gen. Counsel & Corp Sec. 45,000
Chief People Strategy Officer 41,754
Chief Legal Officer 37,648
Executive Vice President & CMO 37,014
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 INSM quote page; the site-wide leaderboard is on the insider transactions hub.