Director Leo Lee (NASDAQ: INSM) receives 3,305 RSUs equity grant

Filing Impact

(Neutral)

Filing Sentiment

(Neutral)

Form Type

Rhea-AI Filing Summary

LEE LEO reported acquisition or exercise transactions in this Form 4 filing.

Insmed Inc director Leo Lee reported receiving a grant of 3,305 shares of Common Stock in the form of Restricted Stock Units (RSUs) on May 13, 2026 for no cash consideration. Each RSU represents a contingent right to one share and vests in full on the first anniversary of the grant date if he remains on the Board through the earlier of that date or the company’s Annual Shareholder Meeting in that year, and attends at least 75% of Board meetings during the period. After this grant and an 11‑share downward correction for a prior clerical error, Lee beneficially owns 57,971 shares directly.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider LEE LEO

Role null

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	3,305	$0.00	--

Holdings After Transaction: Common Stock — 57,971 shares (Direct, null)

Footnotes (1)

Represents Restricted Stock Units (RSUs), each representing a contingent right to receive one share of Common Stock. The RSUs vest in full on the first anniversary of the grant date (the Vesting Date), provided that the director (a) remains a member of the Board of Directors of the issuer until the earlier of (i) such Vesting Date and (ii) the Company's Annual Shareholder Meeting in the year of such Vesting Date, and (b) attends at least 75% of the meetings of the Board of Directors which take place between the grant date and the first anniversary of the grant date. Each RSU was granted on May 13, 2026, for no consideration. Due to a clerical error, this number was previously overstated by 11 shares. This value reflects the adjustment, decreasing the amount beneficially owned by 11 shares.

Key Figures

RSU grant size: 3,305 RSUs Shares after transaction: 57,971 shares Clerical correction: 11 shares +1 more

4 metrics

RSU grant size 3,305 RSUs Granted May 13, 2026

Shares after transaction 57,971 shares Beneficially owned following RSU grant and correction

Clerical correction 11 shares Reduction in previously reported beneficial ownership

Grant price $0.00 per share RSUs granted for no consideration

Key Terms

Restricted Stock Units (RSUs), Vesting Date, Annual Shareholder Meeting, beneficially owned

4 terms

Restricted Stock Units (RSUs) financial

"Represents Restricted Stock Units (RSUs), each representing a contingent right to receive one share of Common Stock."

Restricted stock units (RSUs) are a type of company promise to give employees shares of stock in the future, usually after certain conditions like working for a set time. They are like a gift promised today that you receive later, which can become valuable if the company's stock price goes up. RSUs matter because they are a way companies reward employees and can be a significant part of compensation.

Vesting Date financial

"The RSUs vest in full on the first anniversary of the grant date (the Vesting Date)."

Annual Shareholder Meeting financial

"remains a member of the Board of Directors of the issuer until the earlier of such Vesting Date and the Company's Annual Shareholder Meeting in the year of such Vesting Date"

A yearly gathering where a company’s owners (shareholders) and its leaders meet to review performance, approve key decisions like electing directors, and vote on issues such as executive pay or major policy changes. Think of it as an annual town hall for people who own part of the business: investors use it to ask questions, influence direction through votes, and gauge management’s plans and transparency, all of which can affect the stock’s outlook.

beneficially owned financial

"This value reflects the adjustment, decreasing the amount beneficially owned by 11 shares."

Beneficially owned describes securities or assets where a person has the economic rights and control—such as the right to receive dividends and to direct voting—even if legal title is held in another name. Think of it like having the keys and using a car that’s registered to someone else: you get the benefits and make decisions. Investors care because beneficial ownership reveals who truly controls value and voting power, affecting corporate decisions and takeover dynamics.

Form 4 Insider Transactions: What Each Field Means →

05/15/2026 - 04:07 PM

SEC Form 4

FORM 4

UNITED 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).

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^*

LEE LEO

(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)

X	Director	10% Owner
	Officer (give title below)	Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/13/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form 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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	05/13/2026		A		3,305⁽¹⁾	A	⁽²⁾	57,971⁽³⁾	D

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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. Represents Restricted Stock Units (RSUs), each representing a contingent right to receive one share of Common Stock. The RSUs vest in full on the first anniversary of the grant date (the Vesting Date), provided that the director (a) remains a member of the Board of Directors of the issuer until the earlier of (i) such Vesting Date and (ii) the Company's Annual Shareholder Meeting in the year of such Vesting Date, and (b) attends at least 75% of the meetings of the Board of Directors which take place between the grant date and the first anniversary of the grant date.

2. Each RSU was granted on May 13, 2026, for no consideration.

3. Due to a clerical error, this number was previously overstated by 11 shares. This value reflects the adjustment, decreasing the amount beneficially owned by 11 shares.

Remarks:

	/s/ Leo Lee, by Michael A. Smith as Attorney-in-fact	05/15/2026
	** Signature of Reporting Person	Date
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)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transaction did INSM director Leo Lee report on this Form 4?

Director Leo Lee reported receiving a grant of 3,305 Restricted Stock Units, each representing one share of Insmed Common Stock. The award was granted for no cash consideration and is part of his equity-based director compensation.

When do Leo Lee’s 3,305 RSUs in INSM vest and what are the conditions?

The 3,305 RSUs vest in full on the first anniversary of the May 13, 2026 grant date. Vesting requires Lee to remain on the Board and attend at least 75% of Board meetings during the one-year period.

How many Insmed (INSM) shares does Leo Lee hold after this RSU grant?

Following the reported RSU grant, Leo Lee beneficially owns 57,971 shares of Insmed Common Stock directly. This figure reflects an 11‑share downward adjustment to correct a prior clerical overstatement of his ownership.

Did Leo Lee pay anything for the 3,305 RSUs reported for INSM?

No cash was paid for the 3,305 RSUs; they were granted for no consideration as equity compensation. Each RSU provides a contingent right to receive one share of Insmed Common Stock upon vesting, subject to service and attendance conditions.

What clerical error was corrected in Leo Lee’s reported INSM shareholdings?

A prior filing overstated Leo Lee’s beneficial ownership by 11 shares due to a clerical error. The current Form 4 reduces his reported holdings by 11 shares so the post-transaction total accurately reflects 57,971 shares owned.