INSMED Inc — Director's Dealing 2026

Jan 6, 2026

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: INSMED Inc (INSM)
CIK: 0001104506
Period of Report: 2026-01-02

Reporting Person: Flammer Martina M.D. (Chief Medical Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2026-01-02	Common Stock	A	5998	—	Acquired	89109	Direct
2026-01-02	Common Stock	A	5645	—	Acquired	94754	Direct
2026-01-05	Common Stock	M	4358	$19.74	Acquired	99112	Direct
2026-01-05	Common Stock	M	7945	$29.13	Acquired	107057	Direct
2026-01-05	Common Stock	S	2799	$169.29	Disposed	104258	Direct
2026-01-05	Common Stock	S	3205	$170.61	Disposed	101053	Direct
2026-01-05	Common Stock	S	2836	$171.19	Disposed	98217	Direct
2026-01-05	Common Stock	S	286	$171.92	Disposed	97931	Direct
2026-01-05	Common Stock	S	1820	$173.45	Disposed	96111	Direct
2026-01-05	Common Stock	S	655	$174.28	Disposed	95456	Direct
2026-01-05	Common Stock	S	702	$175.73	Disposed	94754	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2026-01-02	Stock Option (right to buy)	$177.12	A	31280	Acquired	2036-01-02	Common Stock (31280)	Direct
2026-01-05	Stock Option (right to buy)	$19.74	M	4358	Disposed	2033-01-05	Common Stock (4358)	Direct
2026-01-05	Stock Option (right to buy)	$29.13	M	7945	Disposed	2034-01-04	Common Stock (7945)	Direct

Footnotes

F1: 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.

F2: Each RSU was granted on January 2, 2026 for no consideration.

F3: 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.

F4: 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.

F5: 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.

F6: 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.

F7: 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.

F8: 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.

F9: 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.

F10: 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.

F11: 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.

F12: 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.