INSMED Inc — Director's Dealing 2026

Jan 8, 2026

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: INSMED Inc (INSM)
CIK: 0001104506
Period of Report: 2026-01-06

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

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2026-01-06	Common Stock	M	8570	$26.43	Acquired	103324	Direct
2026-01-06	Common Stock	S	4783	$173.47	Disposed	98541	Direct
2026-01-06	Common Stock	S	2830	$174.21	Disposed	95711	Direct
2026-01-06	Common Stock	S	957	$175.01	Disposed	94754	Direct
2026-01-06	Common Stock	S	1615	$173.33	Disposed	93139	Direct
2026-01-07	Common Stock	S	1434	$175.84	Disposed	91705	Direct
2026-01-08	Common Stock	S	1660	$173.87	Disposed	90045	Direct
2026-01-08	Common Stock	S	3251	$174.17	Disposed	86794	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2026-01-06	Stock Option (right to buy)	$26.43	M	8570	Disposed	2032-01-06	Common Stock (8570)	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 4,783 shares sold at prices ranging from $172.89 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.

F3: This is the weighted average sales price representing 2,830 shares sold at prices ranging from $173.92 to $174.80 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 957 shares sold at prices ranging from $174.97 to $175.12 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.

F5: Shares sold to satisfy tax withholding obligations upon the vesting of Restricted Stock Units and to cover related broker fees.

F6: This is the weighted average sales price representing 1,434 shares sold at prices ranging from $175.72 to $176.00 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 1,660 shares sold at prices ranging from $173.87 to $173.90 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.

F8: 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.