INSMED Inc — Director's Dealing 2025

Dec 5, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: INSMED Inc (INSM)
CIK: 0001104506
Period of Report: 2025-12-04

Reporting Person: Lewis William (Director, Chair and CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-12-04	Common Stock	M	6259	$30.46	Acquired	310170	Direct
2025-12-04	Common Stock	M	4440	$17.16	Acquired	314610	Direct
2025-12-04	Common Stock	S	4516	$204.62	Disposed	310094	Direct
2025-12-04	Common Stock	S	2222	$205.66	Disposed	307872	Direct
2025-12-04	Common Stock	S	2921	$206.49	Disposed	304951	Direct
2025-12-04	Common Stock	S	1040	$207.42	Disposed	303911	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-12-04	Stock Option (right to buy)	$30.46	M	6259	Disposed	2028-01-04	Common Stock (6259)	Direct
2025-12-04	Stock Option (right to buy)	$17.16	M	4440	Disposed	2027-05-17	Common Stock (4440)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	233924	Indirect
Common Stock	50500	Indirect

Footnotes

F1: This transaction was effected pursuant to a 10b5-1 trading plan adopted by the Reporting Person on September 4, 2025, in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F2: This is the weighted average sales price representing 4,516 shares sold at prices ranging from $204.01 to $204.98 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.

F3: This is the weighted average sales price representing 2,222 shares sold at prices ranging from $205.11 to $206.02 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.

F4: This is the weighted average sales price representing 2,921 shares sold at prices ranging from $206.15 to $207.13 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.

F5: This is the weighted average sales price representing 1.040 shares sold at prices ranging from $207.20 to $207.73 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.

F6: The options became exercisable based on the following vesting schedule: 25% vested on the first anniversary of the grant date and an additional 12.5% vested on each sixth month anniversary date thereafter through the fourth anniversary of the date of grant. All options are currently exercisable.