X0306 4 2020-01-03 0001104506 INSMED Inc INSM 0001685904 Adsett Roger 700 US HIGHWAY 202/206 BRIDGEWATER NJ 08807 0 1 0 0 Chief Operating Officer Common Stock 2020-01-03 4 A 0 26315 A 94135 D Common Stock 2020-01-03 4 F 0 1414 23.75 D 92721 D Stock Option (right to buy) 23.75 2020-01-03 4 A 0 141300 0 A 2030-01-03 Common Stock 141300 141300 D Restricted stock units granted pursuant to the Company's 2019 Incentive Plan. The Restricted Stock Units vest and become available as follows: twenty five (25%) percent on each anniversary of the date of grant through the fourth anniversary date of the grant. Each Restricted Stock Unit was received as a grant on January 3, 2020, for no consideration, and represents a contingent right to receive one share of Common Stock. Shares withheld by the Company to satisfy tax withholding requirements on vesting of time-based restricted stock units. Stock options granted under the Company's 2019 Incentive Plan. The options become exercisable based on the following vesting schedule: twenty five percent (25%) on the first anniversary of the grant date and an additional twelve and one half percent (12.5%) vest on each sixth month anniversary date thereafter through the fourth anniversary of the date of grant. /s/ Roger Adsett, by Christine Pellizzari as Attorney-in-fact 2020-01-07