Welcome to our dedicated page for INSMED SEC filings (Ticker: INSM), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Insmed Incorporated filings document formal disclosures for its commercial biopharmaceutical portfolio and respiratory and inflammatory pipeline. Recent Form 8-K reports furnish financial results, investor presentations, Regulation FD materials, clinical-study updates for ARIKAYCE and brensocatib, regulatory approval announcements for BRINSUPRI, and portfolio additions such as INS1148.
The company’s proxy materials describe board elections, executive compensation, equity awards, shareholder voting matters and governance practices. Other current reports document compensatory arrangements, director-transition disclosures, exhibits and Inline XBRL cover-page data tied to Insmed’s Nasdaq-listed common stock.
Insmed Inc.’s Chief Medical Officer Martina Flammer reported a series of stock transactions. On February 2, 2026, she exercised a stock option for 7,982 shares of common stock at $65.72 per share and sold multiple blocks of common stock under a Rule 10b5-1 trading plan, at weighted average prices including $152.06, $153.16, $154.56, $155.46 and $156.86 per share. On February 3, 2026, she sold 795 shares at $155.77 per share to satisfy tax withholding and related broker fees upon RSU vesting. After these transactions, she directly owned 84,112 shares of common stock and held 23,948 stock options.
Insmed common stockholder files notice to sell shares under Rule 144. The filing covers a planned sale of 791 common shares of Insmed through Merrill Lynch on the NASDAQ, with an aggregate market value of 123,526 and 213,273,469 shares outstanding.
The shares to be sold were acquired on 02/01/2026 via stock plan activity from the issuer. The notice also lists recent sales by Roger Adsett during January 2026, including 2,059 common shares for gross proceeds of 358,616, 802 shares for 140,406, and 1,429 shares for 247,688.
A shareholder of INSM has filed a notice under Rule 144 to sell 640 shares of common stock through Merrill Lynch on the NASDAQ, with an approximate sale date of 02/03/2026. The shares were acquired on 02/01/2026 via stock plan activity from the issuer.
The notice also lists earlier sales by Michael Smith over the past three months, including 27,130 common shares sold on 11/03/2025 for gross proceeds of 4,985,054, alongside several smaller sales in January 2026.
William Lewis filed a notice of proposed sale under Rule 144 to sell 3,009 shares of common stock through Merrill Lynch in Washington, DC. The shares are listed on NASDAQ, and the approximate sale date stated is February 3, 2026.
The shares to be sold were acquired on February 1, 2026 via stock plan activity from the issuer. Over the prior three months, William Lewis reported several other common stock sales, including blocks of 19,215 and 10,699 shares, with disclosed gross proceeds for each transaction.
INSM insider Martina Flammer filed a notice to sell 795 shares of common stock through Merrill Lynch on or about 02/03/2026 on NASDAQ, with an aggregate market value of 123,837 and 213,273,469 shares outstanding. The 795 shares were acquired on 02/01/2026 via stock plan activity from the issuer.
Over the prior three months, Flammer has sold multiple blocks of INSM common stock, including 31,226 shares on 11/11/2025 for gross proceeds of 5,921,820 and 12,303 shares on 01/05/2026 for gross proceeds of 2,108,459.
Insmed insider Sara Bonstein has filed a Form 144 notice to sell 748 shares of common stock. The shares are to be sold through Merrill Lynch on the NASDAQ around 02/03/2026, with an aggregate market value of 116,938 based on the figure reported.
The 748 shares were acquired on 02/01/2026 through stock plan activity directly from the issuer. Over the prior three months, Bonstein reported additional sales of common stock, including 1,447 shares on 01/08/2026, 1,678 shares on 01/07/2026, and 1,517 shares on 01/06/2026, with gross proceeds of 252,023, 293,766, and 262,941, respectively.
Insmed (INSM) insider Martina Flammer has filed a Form 144 indicating an intention to sell 7,982 shares of the company’s common stock. The planned sale, through Merrill Lynch in Washington, D.C., has an aggregate market value of 1,233,964 and is listed for execution on 02/02/2026 on the NASDAQ.
The shares were acquired on 02/02/2026 via stock plan activity from the issuer. The notice also shows prior sales over the past three months, including 31,226 common shares sold on 11/11/2025 for gross proceeds of 5,921,820.
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.
BlackRock, Inc. has reported a significant ownership position in Insmed Inc. common stock. As of 12/31/2025, BlackRock beneficially owned 14,121,445 shares, representing 6.6% of the outstanding common stock. It held sole voting power over 13,203,800 shares and sole dispositive power over all 14,121,445 shares, with no shared voting or dispositive authority.
The shares are held across various BlackRock business units, and a range of underlying clients have rights to dividends and sale proceeds, but no single client has more than five percent of Insmed’s total outstanding common shares. BlackRock states that the holdings are in the ordinary course of business and not for the purpose of changing or influencing control of Insmed.
William Lewis filed a Rule 144 notice to sell 10,699 shares of common stock through Merrill Lynch on or about 01/20/2026, with the shares listed on NASDAQ. The filing shows these 10,699 shares were acquired from the issuer on 01/20/2026 via stock plan activity, with payment on the same date. The notice also lists the issuer’s common stock with 213,273,469 shares outstanding.
The document details prior sales by William Lewis over the past three months, including multiple common stock transactions between 12/04/2025 and 01/12/2026 with individual sale amounts ranging from 2,357 to 19,215 shares and corresponding gross proceeds disclosed for each trade.