[144] Insmed, Inc. SEC Filing

Rhea-AI Filing Summary

Insmed, Inc. (NASDAQ: INSM) – Form 144 filing dated 07/07/2025

The notice discloses that insider Sara Bonstein intends to sell 57,764 shares of Insmed common stock through Merrill Lynch (1800 K St NW, Washington DC) on or about July 7, 2025. At the indicated market price, the proposed transaction represents an aggregate value of approximately $5.54 million. Total shares outstanding are reported at 182,138,923, so the planned sale equals roughly 0.03 % of common shares outstanding.

Recent insider liquidity activity (last three months, same filer):

• 06/23/2025 – 57,765 shares sold for $5,877,431
• 06/10/2025 – 57,766 shares sold for $5,146,207
• 06/03/2025 – 1,579 shares sold for $112,898
• 05/14/2025 – 1,634 shares sold for $107,206
• 05/13/2025 – 8,870 shares sold for $601,474

Including the proposed sale, the insider will have disposed of 185,378 shares for total gross proceeds of about $17.38 million since May 2025.

No information is provided regarding the insider’s relationship to the issuer, the existence of a Rule 10b5-1 trading plan, or motivations for the transactions. The filing states that the seller attests to not possessing undisclosed material adverse information.

Positive

• None.

Negative

• Repeated sizable insider sales: 185,378 shares (~$17.4 m) sold or planned within three months may signal reduced insider confidence.
• Lack of disclosed 10b5-1 plan leaves uncertainty about whether the sales are systematic or opportunistic.

Insights

Insider-Trading Analyst

TL;DR: Form 144 shows continued large insider sales; sentiment skewed negative due to size and frequency.

The filer, Sara Bonstein, has already liquidated roughly 127.6 k shares over the past three months and now intends to dispose of another 57.8 k shares worth $5.5 m. While the stake equals only 0.03 % of shares outstanding, the repetitive pattern and cumulative $17 m proceeds can be viewed as a bearish signal on near-term share performance, especially absent offsetting insider purchases. The filing lacks mention of a Rule 10b5-1 plan, leaving uncertainty around pre-scheduled versus discretionary selling. Investors often interpret such clustered sales as waning insider confidence or forthcoming personal diversification. Impact is negative but not highly material to capital structure given Insmed’s >182 m share float.

Form 144 Filer Information	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 144 NOTICE OF PROPOSED SALE OF SECURITIES PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
FORM 144

144: Filer Information

Filer CIK
Filer CCC
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer

SEC File Number

Address of Issuer

Phone

Name of Person for Whose Account the Securities are To Be Sold

See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice.

Relationship to Issuer

144: Securities Information

Title of the Class of Securities To Be Sold	Name and Address of the Broker	Number of Shares or Other Units To Be Sold	Aggregate Market Value	Number of Shares or Other Units Outstanding	Approximate Date of Sale	Name the Securities Exchange
Common	Merrill Lynch 1800 K ST NW Suite 800 Washington DC 20006	57764	5535591.00	182138923	07/07/2025	NASDAQ

Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor:

144: Securities To Be Sold

Title of the Class	Date you Acquired	Nature of Acquisition Transaction	Name of Person from Whom Acquired	Is this a Gift?	Date Donor Acquired	Amount of Securities Acquired	Date of Payment	Nature of Payment *
Common	07/07/2025	Stock Plan Activity	Issuer			47888	07/07/2025	n/a
Common	05/11/2024	Stock Plan Activity	Issuer			3777	05/11/2024	n/a
Common	05/12/2024	Stock Plan Activity	Issuer			1915	05/12/2024	n/a
Common	01/04/2025	Stock Plan Activity	Issuer			410	01/04/2025	n/a
Common	05/11/2025	Stock Plan Activity	Issuer			2824	05/11/2025	n/a
Common	05/12/2025	Stock Plan Activity	Issuer			458	05/12/2025	n/a
Common	06/01/2025	Stock Plan Activity	Issuer			492	06/01/2025	n/a

* If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid.

Furnish the following information as to all securities of the issuer sold during the past 3 months by the person for whose account the securities are to be sold.

144: Securities Sold During The Past 3 Months

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
Sara Bonstein 700 US Highway 202/206 Bridgewater NJ 08807	Common	06/23/2025	57765	5877431.00
Sara Bonstein 700 US Highway 202/206 Bridgewater NJ 08807	Common	06/10/2025	57766	5146207.00
Sara Bonstein 700 US Highway 202/206 Bridgewater NJ 08807	Common	06/03/2025	1579	112898.00
Sara Bonstein 700 US Highway 202/206 Bridgewater NJ 08807	Common	05/14/2025	1634	107206.00
Sara Bonstein 700 US Highway 202/206 Bridgewater NJ 08807	Common	05/13/2025	8870	601474.00

144: Remarks and Signature

Remarks

Date of Notice

Date of Plan Adoption or Giving of Instruction, If Relying on Rule 10b5-1

ATTENTION:

The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. If such person has adopted a written trading plan or given trading instructions to satisfy Rule 10b5-1 under the Exchange Act, by signing the form and indicating the date that the plan was adopted or the instruction given, that person makes such representation as of the plan adoption or instruction date.

Signature

ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)

FAQ

How many Insmed (INSM) shares are proposed for sale in the July 7 2025 Form 144?

The filing covers 57,764 common shares.

What is the estimated value of the proposed INSM share sale?

Aggregate market value is approximately $5.54 million.

Who is the insider selling Insmed shares according to the Form 144?

The seller named is Sara Bonstein.

How many INSM shares has the insider sold in the past three months?

The insider previously sold 127,614 shares for about $11.85 million.

What percentage of Insmed’s shares outstanding does the upcoming sale represent?

Roughly 0.03 % of the 182,138,923 shares outstanding.

Which brokerage firm will execute the planned sale?

The trades are to be executed through Merrill Lynch, Washington DC.