X0508 4 2026-01-02 0 0001104506 INSMED Inc INSM 0001796960 Flammer Martina M.D. 700 US HIGHWAY 202/206 BRIDGEWATER NJ 08807 0 1 0 0 Chief Medical Officer 1 Common Stock 2026-01-02 4 A 0 5998 A 89109 D Common Stock 2026-01-02 4 A 0 5645 A 94754 D Common Stock 2026-01-05 4 M 0 4358 19.74 A 99112 D Common Stock 2026-01-05 4 M 0 7945 29.13 A 107057 D Common Stock 2026-01-05 4 S 0 2799 169.29 D 104258 D Common Stock 2026-01-05 4 S 0 3205 170.61 D 101053 D Common Stock 2026-01-05 4 S 0 2836 171.19 D 98217 D Common Stock 2026-01-05 4 S 0 286 171.92 D 97931 D Common Stock 2026-01-05 4 S 0 1820 173.45 D 96111 D Common Stock 2026-01-05 4 S 0 655 174.28 D 95456 D Common Stock 2026-01-05 4 S 0 702 175.73 D 94754 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 Stock Option (right to buy) 19.74 2026-01-05 4 M 0 4358 0 D 2033-01-05 Common Stock 4358 8715 D Stock Option (right to buy) 29.13 2026-01-05 4 M 0 7945 0 D 2034-01-04 Common Stock 7945 31780 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. Represents 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 in full on February 1, 2029. This transaction was effected pursuant to a 10b5-1 trading plan adopted by the Reporting Person on February 27, 2025 in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended. This is the weighted average sales price representing 2,799 shares sold at prices ranging from $168.88 to $169.69 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. This is the weighted average sales price representing 3,205 shares sold at prices ranging from $169.91 to $170.90 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. This is the weighted average sales price representing 2,836 shares sold at prices ranging from $170.91 to $171.89 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. This is the weighted average sales price representing 1,820 shares sold at prices ranging from $173.05 to $173.87 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. This is the weighted average sales price representing 655 shares sold at prices ranging from $174.20 to $174.43 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. This is the weighted average sales price representing 702 shares sold at prices ranging from $175.54 to $176.12 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. 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. The options become exercisable based on the following vesting schedule: 25% vest on the first anniversary of the grant date and an additional 12.5% vest on each sixth month anniversary date thereafter through the fourth anniversary of the date of grant. /s/ Martina Flammer, M.D., by Michael A. Smith as Attorney-in-fact 2026-01-06