X0508 4 2026-01-02 0 0001104506 INSMED Inc INSM 0001685904 Adsett Roger 700 US HIGHWAY 202/206 BRIDGEWATER NJ 08807 0 1 0 0 Chief Operating Officer 0 Common Stock 2026-01-02 4 A 0 5998 A 111891 D Stock Option (right to buy) 177.12 2026-01-02 4 A 0 31280 0 A 2036-01-02 Common Stock 31280 31280 D Represents Restricted Stock Units (RSUs), each representing a contingent right to receive one share of Common Stock, granted pursuant to the Company's Amended and Restated 2019 Incentive Plan, as amended. The RSUs vest as follows: 25% on the first day of the first month following the first anniversary of the date of grant (the Initial Vesting Date) and 25% on each anniversary of the Initial Vesting Date until fully vested. Each RSU was granted on January 2, 2026 for no consideration. Includes 256 shares acquired through the Company's 2018 Employee Stock Purchase Plan. These stock options were granted under the Company's Amended and Restated 2019 Incentive Plan, as amended. The options become exercisable based on the following vesting schedule: 25% vest on the Initial Vesting Date and an additional 12.5% vest every six months thereafter until fully vested. /s/ Roger Adsett, by Michael A. Smith as Attorney-in-fact 2026-01-06