Every Form 4 that Insmed, Inc. (INSM) has filed with the SEC in the last 12 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A Form 4 covers the transactions officers, directors and large holders report, so if you follow INSM and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full INSM filings page.
Insmed Inc. Chair and CEO William Lewis reported a series of option exercises and related stock sales on January 20, 2026 under a pre-arranged Rule 10b5-1 trading plan adopted on September 4, 2025. He exercised stock options to acquire 6,259 shares at an exercise price of $30.46 per share and 4,440 shares at $17.16 per share, both at a cost of $0 per derivative security.
On the same date, Lewis reported open-market sales of Insmed common stock in several tranches, including 1,006 shares at a weighted average price of $156.80, 1,243 shares at $158.37, 5,967 shares at $158.99, 2,229 shares at $159.85, and 254 shares at $160.70, with each weighted average representing sales within stated price ranges. Following these transactions, Lewis directly owned 306,891 shares of common stock and held options covering 75,109 and 53,280 shares in two grants. The filing also reports indirect ownership of 233,924 shares through the Katie Procter Dynasty Trust and 50,500 shares through the William Lewis Family Legacy Trust.
Insmed Inc. (INSM) Chair and CEO William Lewis reported a series of option exercises and related stock sales on January 12, 2026, under a pre-arranged Rule 10b5-1 trading plan adopted on September 4, 2025. He exercised stock options for 6,259 shares of common stock at $30.46 per share and 4,440 shares at $17.16 per share, converting these into common shares.
On the same date he sold multiple blocks of Insmed common stock, including 3,974 shares at a weighted average price of $167.73 and 7,176 shares at $168.63, with additional smaller sales up to $174.86 per share. After these transactions, he directly owned 306,891 shares of common stock and indirectly held 233,924 shares through the Katie Procter Dynasty Trust and 50,500 shares through the William Lewis Family Legacy Trust. He also held 81,368 and 57,720 stock options remaining from the exercised grants.
Insmed Inc.'s Chief Medical Officer, Martina Flammer, reported a sale of company common stock. On January 9, 2026, she sold 1,887 shares of Insmed common stock at a price of $186.19 per share, as shown in Table I of the filing.
The filing states that this transaction was carried out under a pre-arranged Rule 10b5-1 trading plan adopted on February 27, 2025. After this sale, Flammer beneficially owns 84,907 shares of Insmed common stock, held directly.
Insmed Inc. Chief Operating Officer Roger Adsett reported three sales of Insmed common stock in early January. On January 6, 2026, he sold 1,429 shares at $173.33 per share. On January 7, 2026, he sold 802 shares at $175.07 per share, and on January 8, 2026, he sold 2,059 shares at $174.17 per share.
After these transactions, Adsett directly held 107,601 Insmed shares. A footnote explains that the shares were sold to satisfy tax withholding obligations arising from the vesting of restricted stock units and to cover related broker fees, indicating these were primarily tax-related transactions rather than discretionary sales.
Insmed Inc. reported that its Chief Financial Officer, Sara Bonstein, sold small blocks of common stock on three consecutive days to cover tax obligations tied to equity awards. On January 6, 2026, she sold 1,517 shares at $173.33 per share, on January 7, 2026 she sold 1,678 shares at $175.07 per share, and on January 8, 2026 she sold 1,447 shares at $174.17 per share. According to the filing, these sales were made to satisfy tax withholding obligations upon the vesting of restricted stock units and to cover related broker fees, and she directly owned 80,506 shares of common stock after the final transaction.
Insmed Inc.'s Chief Medical Officer, Martina Flammer, M.D., reported a series of equity transactions in company stock. On January 6, 2026, she exercised a stock option for 8,570 shares of common stock at an exercise price of $26.43 per share, converting a derivative position into directly held stock. That same day, she reported open-market sales of common stock, including 4,783 shares at a weighted average price of $173.47, 2,830 shares at $174.21, and 957 shares at $175.01.
Additional sales included 1,615 shares at $173.33 on January 6, 1,434 shares at a weighted average of $175.84 on January 7, and on January 8, 1,660 shares at a weighted average of $173.87 and 3,251 shares at $174.17. A portion of the shares sold was specifically to satisfy tax withholding obligations upon vesting of restricted stock units and related broker fees. After these transactions, she directly held 86,794 shares of Insmed common stock. All trades noted as (1) were effected under a Rule 10b5-1 trading plan adopted on February 27, 2025.
Insmed Chair and CEO William Lewis reported three sales of Insmed common stock on January 6–8, 2026. He sold 4,096 shares on January 6 at $173.33, 2,357 shares on January 7 at $175.07, and 3,223 shares on January 8 at $174.17, all reported as open market sales.
According to the filing, these shares were sold to satisfy tax withholding obligations upon the vesting of Restricted Stock Units and to cover related broker fees. After these transactions, Lewis directly held 315,407 shares of Insmed common stock. He also had indirect beneficial ownership of 233,924 shares held by the Katie Procter Dynasty Trust and 50,500 shares held by the William Lewis Family Legacy Trust.
Insmed's chief legal officer reports small share sales tied to tax withholding. Michael Alexander Smith, Chief Legal Officer of Insmed Inc., reported three sales of common stock on January 6–8, 2026. He sold 1,396 shares at $173.33, 709 shares at $175.07, and 1,053 shares at $174.17. After these transactions, he directly beneficially owned 57,037 shares of Insmed common stock. A footnote explains that the shares were sold to satisfy tax withholding obligations upon the vesting of restricted stock units and to cover related broker fees, indicating the sales were driven by tax requirements rather than discretionary trading.
Insmed’s Chief Legal Officer Michael Alexander Smith received new equity awards. On January 2, 2026, he was granted 5,293 Restricted Stock Units (RSUs), each equal to one share of common stock, under Insmed’s Amended and Restated 2019 Incentive Plan. The RSUs vest 25% on the first day of the first month following the first anniversary of the grant date, then 25% on each anniversary of that initial vesting date until fully vested. The grant increased his directly held common stock to 60,195 shares.
On the same date, he was also granted 27,600 stock options with an exercise price of $177.12 per share, expiring on January 2, 2036. These options vest 25% on the initial vesting date, with an additional 12.5% every six months thereafter until fully exercisable. Following this grant, he holds 27,600 stock options directly.
Insmed Inc. (INSM) reported an insider transaction on a Form 4 filing. A company director sold 5,000 shares of Insmed common stock on November 24, 2025, identified with transaction code "S" for a sale. The shares were sold at a price of $204.58 per share in an open market transaction.
After this sale, the director beneficially owns 58,729 shares of Insmed common stock, held directly. The filing reflects a routine update to the director’s ownership position and does not report any derivative securities activity.
Insmed Inc director Leo Lee reported multiple sales of Insmed Common Stock on November 17, 2025, totaling 75,000 shares. Footnotes describe weighted average sale prices ranging from $193.00 to $197.78 per share. After these trades, Lee directly held 54,677 Insmed common shares.
Insmed Inc. (INSM) reported an insider stock sale by a company director. On 11/14/2025, the director sold 10,000 shares of common stock at a price of $195.87 per share, according to a Form 4 filing. After this transaction, the director continues to hold 63,729 shares directly. This filing simply records a change in the director’s personal holdings and does not, by itself, change the company’s operations or financial results.
Insmed (INSM) reported an insider transaction by its Chief People Strategy Officer on 11/12/2025. The officer exercised 30,000 stock options at an exercise price of $26.46 and received common shares. On the same day, the officer sold shares in four tranches at weighted average prices of $192.45 (4,078 shares), $193.64 (6,575), $194.44 (19,183), and $195.88 (164), with ranges disclosed for each tranche. Following these transactions, the officer directly owned 36,461 common shares. Remaining derivative holdings were 15,760 options expiring on 05/12/2031, which are currently exercisable as described.
Insmed Inc. (INSM) reported insider transactions by its Chief Medical Officer on 11/11/2025. The officer exercised stock options for 12,949 shares at $17.07 and 18,277 shares at $18.95 (transaction code M), then sold shares in open-market trades (transaction code S) under a Rule 10b5-1 plan adopted on February 27, 2025.
Sales were executed at weighted average prices of $188.38 for 5,467 shares (range $187.93–$188.90), $189.36 for 12,224 shares (range $188.90–$189.88), $190.33 for 10,622 shares (range $189.92–$190.90), and $191.04 for 2,913 shares (range $190.94–$191.14). Following these transactions, the officer reported 83,111 shares beneficially owned directly. The disclosed options carry expirations on 05/11/2032 and 05/11/2033, with vesting at 25% on the first anniversary and 12.5% each six months through the fourth anniversary.
Insmed (INSM) filed a Form 4 disclosing a gift transfer by a director. On 11/06/2025, the reporting person executed a Code G transaction, gifting 60,000 shares of common stock at $0.
Following the transaction, the director held 66,933 shares directly and 60,000 shares indirectly, listed as held by spouse revocable trust. The filing indicates a change in the form of ownership, not an open-market trade.
Insmed (INSM) reported an insider transaction by its Chief Legal Officer. On 11/03/2025, the officer exercised 27,130 stock options at an exercise price of $23.75 and sold shares in multiple tranches under a Rule 10b5-1 trading plan adopted on February 27, 2025.
The sales were executed at weighted average prices ranging from $181.01 to $187.97, with the filing noting price ranges and an undertaking to provide per-price breakdowns upon request. Following the reported transactions, the officer beneficially owned 54,902 shares directly.