X0508 4 2025-11-17 0 0001104506 INSMED Inc INSM 0001740789 LEE LEO 700 US HIGHWAY 202/206 BRIDGEWATER NJ 08807 1 0 0 0 0 Common Stock 2025-11-17 4 S 0 3212 193.51 D 126465 D Common Stock 2025-11-17 4 S 0 17594 194.49 D 108871 D Common Stock 2025-11-17 4 S 0 14944 195.39 D 93927 D Common Stock 2025-11-17 4 S 0 24076 196.61 D 69851 D Common Stock 2025-11-17 4 S 0 15174 197.40 D 54677 D This is the weighted average sales price representing 3,212 shares sold at prices ranging from $193.00 to $193.99 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 17,594 shares sold at prices ranging from $194.00 to $194.99 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 14,944 shares sold at prices ranging from $195.00 to $195.99 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 24,076 shares sold at prices ranging from $196.00 to $196.99 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 15,174 shares sold at prices ranging from $197.00 to $197.78 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. Exhibit List - Exhibit 24 - Power of Attorney /s/ Leo Lee, by Michael A. Smith as Attorney-in-fact 2025-11-18