INSMED Inc — Director's Dealing 2025

Nov 5, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: INSMED Inc (INSM)
CIK: 0001104506
Period of Report: 2025-11-03

Reporting Person: Smith Michael Alexander (Chief Legal Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-11-03	Common Stock	M	27130	$23.75	Acquired	82032	Direct
2025-11-03	Common Stock	S	1342	$181.01	Disposed	80690	Direct
2025-11-03	Common Stock	S	7619	$181.88	Disposed	73071	Direct
2025-11-03	Common Stock	S	4286	$182.60	Disposed	68785	Direct
2025-11-03	Common Stock	S	4032	$183.92	Disposed	64753	Direct
2025-11-03	Common Stock	S	3243	$184.91	Disposed	61510	Direct
2025-11-03	Common Stock	S	3636	$185.93	Disposed	57874	Direct
2025-11-03	Common Stock	S	1572	$187.15	Disposed	56302	Direct
2025-11-03	Common Stock	S	1400	$187.97	Disposed	54902	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-11-03	Stock Option (right to buy)	$23.75	M	27130	Disposed	2030-01-03	Common Stock (27130)	Direct

Footnotes

F1: 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.

F2: This is the weighted average sales price representing 1,342 shares sold at prices ranging from $180.29 to $181.19 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 7,619 shares sold at prices ranging from $181.30 to $182.29 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 4,286 shares sold at prices ranging from $182.30 to $183.03 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 4,032 shares sold at prices ranging from $183.49 to $184.48 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: This is the weighted average sales price representing 3,243 shares sold at prices ranging from $184.50 to $185.48 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.

F7: This is the weighted average sales price representing 3,636 shares sold at prices ranging from $185.51 to $186.45 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.

F8: This is the weighted average sales price representing 1,572 shares sold at prices ranging from $186.61 to $187.53 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.

F9: This is the weighted average sales price representing 1,400 shares sold at prices ranging from $187.88 to $188.13 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.

F10: 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.