STOCK TITAN

Insmed (INSM) CEO trades 10,700 shares after option exercise

(Neutral)
(Neutral)
Form Type
4

Rhea-AI Filing Summary

INSMED Inc Chair and CEO William Lewis exercised stock options for 10,700 shares of common stock on July 23, 2026, at exercise prices of $30.46 and $17.16, then sold 10,700 shares at weighted average prices of $105.62 and $106.43 under a Rule 10b5-1 trading plan adopted on September 4, 2025. He continues to hold 233,924 shares indirectly through a trust.

Positive

  • None.

Negative

  • None.
Insider Lewis William
Role Chair and CEO
Sold 10,700 shs ($1.13M)
Approx. gross sale proceeds $1.13M
Approx. exercise cost $267K
Approx. pre-tax spread $868K
Type Security Shares Price Value
Exercise Stock Option (right to buy) F1, F4 6,260 $0.00 $0.00
Exercise Stock Option (right to buy) F1, F4 4,440 $0.00 $0.00
Exercise Common Stock F1 6,260 $30.46 $191K
Exercise Common Stock F1 4,440 $17.16 $76K
Sale Common Stock F1, F2 4,828 $105.62 $510K
Sale Common Stock F1, F3 5,872 $106.43 $625K
holding Common Stock -- -- --
Holdings After Transaction: Stock Option (right to buy) — 0 shares (Direct); Common Stock — 259,058 shares (Direct); Common Stock — 233,924 shares (Indirect, By trust)
Footnotes (4)
  1. 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.
  2. 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.
  3. 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.
  4. 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.
Options exercised 6,260 shares at $30.4600 Stock options exercised into common stock; expiration 2028-01-04
Options exercised 4,440 shares at $17.1600 Stock options exercised into common stock; expiration 2027-05-17
Shares sold (block 1) 4,828 shares at $105.6200 Weighted average sale price; actual prices $105.09–$106.02 per share
Shares sold (block 2) 5,872 shares at $106.4300 Weighted average sale price; actual prices $106.09–$106.78 per share
Net shares sold 10,700 shares Total common shares sold in open-market transactions on 2026-07-23
Indirect holdings after transactions 233,924 shares Common stock held indirectly by trust as of 2026-07-23
10b5-1 plan adoption date September 4, 2025 Date William Lewis adopted the Rule 10b5-1 trading plan
Rule 10b5-1 trading plan financial
"transactions were effected pursuant to a 10b5-1 trading plan adopted by the Reporting Person"
A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.
weighted average sales price financial
"This is the weighted average sales price representing 4,828 shares sold"
Stock Option (right to buy) financial
"security_title: Stock Option (right to buy) with underlying Common Stock"
vesting schedule financial
"The options became exercisable based on the following vesting schedule: 25% vested on the first anniversary"
A vesting schedule is a timeline that determines when someone gains full ownership of certain benefits, such as company stock or retirement contributions. Think of it like earning the right to own a gift gradually over time, rather than receiving it all at once. It matters to investors because it affects when they can fully access or sell these benefits, influencing their financial planning and decision-making.
indirect ownership financial
"Common Stock total_shares_following_transaction 233,924.0000 with nature_of_ownership: By trust"

AI-generated analysis. How Rhea-AI works. Not financial advice.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google
Add on Google
Learn about SEC filing dates

FAQ

What insider transactions did Insmed (INSM) CEO William Lewis report on July 23, 2026?

William Lewis exercised stock options for 10,700 shares of Insmed common stock and sold 10,700 shares the same day in open-market transactions, reflecting an option exercise followed by partial monetization of the resulting shares.

Were the Insmed (INSM) stock trades by William Lewis made under a Rule 10b5-1 plan?

Yes. The filing states the transactions were effected under a Rule 10b5-1 trading plan adopted by William Lewis on September 4, 2025, indicating the trades followed a pre-established schedule rather than discretionary same-day decisions.

At what prices did Insmed (INSM) CEO William Lewis sell shares?

Lewis sold 4,828 shares at a weighted average price of $105.62 and 5,872 shares at a weighted average price of $106.43, with actual sale prices ranging between $105.09–$106.02 and $106.09–$106.78 per share, respectively.

How many Insmed (INSM) shares does William Lewis hold after these reported trades?

After the reported transactions, William Lewis is shown as indirectly holding 233,924 shares of Insmed common stock through a trust. This figure reflects indirect ownership as of July 23, 2026, separate from the directly traded shares.

What option grants were exercised in the latest Insmed (INSM) insider filing?

Lewis exercised options covering 6,260 shares at $30.46 per share, expiring January 4, 2028, and 4,440 shares at $17.16 per share, expiring May 17, 2027. These option exercises generated the common shares that were subsequently sold in part.
SEC Form 4
FORM 4UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number:3235-0287
Estimated average burden
hours per response:0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
X
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
Lewis William

(Last)(First)(Middle)
700 US HIGHWAY 202/206

(Street)
BRIDGEWATER NEW JERSEY 08807

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
INSMED Inc [ INSM ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
XDirector10% Owner
XOfficer (give title below)Other (specify below)
Chair and CEO
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
07/23/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year)2A. Deemed Execution Date, if any (Month/Day/Year)3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeVAmount(A) or (D)Price
Common Stock07/23/2026M(1)6,260A$30.46265,318D
Common Stock07/23/2026M(1)4,440A$17.16269,758D
Common Stock07/23/2026S(1)4,828D$105.62(2)264,930D
Common Stock07/23/2026S(1)5,872D$106.43(3)259,058D
Common Stock233,924IBy trust
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year)3A. Deemed Execution Date, if any (Month/Day/Year)4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year)7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Stock Option (right to buy)$30.4607/23/2026M(1)6,260 (4)01/04/2028Common Stock6,260$00D
Stock Option (right to buy)$17.1607/23/2026M(1)4,440 (4)05/17/2027Common Stock4,440$00D
Explanation of Responses:
1. 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.
2. 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.
3. 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.
4. 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.
Remarks:
/s/ William Lewis, by Michael A. Smith as Attorney-in-fact07/24/2026
** Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)