William Lewis - 23 Jul 2026 Form 4 Insider Report for INSMED Inc (INSM)

Reporting relationship: Chair and CEO, Director
Issuer ticker: INSM
Reported as of: 23 Jul 2026
Net transaction value: -$1,134,890
SEC form: 4
Accepted by SEC: 24 Jul 2026, 17:02:28 UTC
Prior SEC filing: 10 Jul 2026
Source filing: View source filing
Reporting owner signature: /s/ William Lewis, by Michael A. Smith as Attorney-in-fact

Key filing fact

William Lewis filed Form 4 for INSMED Inc (INSM) on 24 Jul 2026.

Key facts

This page summarizes William Lewis's Form 4 filing for INSMED Inc (INSM).
6 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 24 Jul 2026, 17:02.

Change

Previous filing in this sequence was filed on 10 Jul 2026.
Current net transaction value: -$1,134,890.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001402051 Primary reporting owner

Lewis William

Relationship: Chair and CEO, Director
Address: 700 US HIGHWAY 202/206, BRIDGEWATER
Signature: /s/ William Lewis, by Michael A. Smith as Attorney-in-fact
Signature date: 24 Jul 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

INSM transaction

Common Stock

Options Exercise

Transaction value
Shares: +6,260
Change %: +2.4%
Price: $30.46^*
Shares after: 265,318
Date: 23 Jul 2026
Ownership: Direct
Footnotes: F1

INSM transaction

Common Stock

Options Exercise

Transaction value
Shares: +4,440
Change %: +1.7%
Price: $17.16^*
Shares after: 269,758
Date: 23 Jul 2026
Ownership: Direct
Footnotes: F1

INSM transaction

Common Stock

Sale

Transaction value: $509,933
Shares: -4,828
Change %: -1.8%
Price: $105.62
Shares after: 264,930
Date: 23 Jul 2026
Ownership: Direct
Footnotes: F1, F2

INSM transaction

Common Stock

Sale

Transaction value: $624,957
Shares: -5,872
Change %: -2.2%
Price: $106.43
Shares after: 259,058
Date: 23 Jul 2026
Ownership: Direct
Footnotes: F1, F3

INSM holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 233,924
Date: 23 Jul 2026
Ownership: By trust

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

INSM transaction Derivative

Stock Option (right to buy)

Options Exercise

Transaction value
Shares: -6,260
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 23 Jul 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 6,260
Exercise price: $30.46
Footnotes: F1, F4

INSM transaction Derivative

Stock Option (right to buy)

Options Exercise

Transaction value
Shares: -4,440
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 23 Jul 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 4,440
Exercise price: $17.16
Footnotes: F1, F4

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 4 footnotes

Footnote 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.

Footnote F2

This is the weighted average sales price representing 4,828 shares sold at prices ranging from $105.09 to $106.02 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.

Footnote F3

This is the weighted average sales price representing 5,872 shares sold at prices ranging from $106.09 to $106.78 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.

Footnote F4

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.