INSM (NASDAQ: INSM) insider details planned Rule 144 share sale

Rhea-AI Filing Summary

A company insider filed a Rule 144 notice to sell 2357 shares of common stock through Merrill Lynch on the NASDAQ, with an approximate sale date of 01/07/2026. These 2357 shares of common stock were acquired on 01/05/2026 through stock plan activity from the issuer.

Over the past three months, the same seller, William Lewis, has already sold additional common shares of the issuer. These sales included 4096 shares on 01/06/2026 for gross proceeds of 709959, and two earlier sales of 10699 shares each on 12/18/2025 and 12/04/2025 for gross proceeds of 1786437 and 2199583, respectively.

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	2357	412636	213273469	01/07/2026	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	01/05/2026	Stock Plan Activity	Issuer			2357	01/05/2026	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
William Lewis 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/06/2026	4096	709959
William Lewis 700 US Highway 202/206 Bridgewater NJ 08807	Common	12/18/2025	10699	1786437
William Lewis 700 US Highway 202/206 Bridgewater NJ 08807	Common	12/04/2025	10699	2199583

144: Remarks and Signature

Remarks

Date of Notice

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

What transaction is disclosed in this Form 144 for INSM?

The notice discloses that a company insider intends to sell 2357 shares of INSM common stock on the NASDAQ through Merrill Lynch, with an approximate sale date of 01/07/2026.

Who is the seller in the INSM Form 144 filing and what is their recent activity?

The seller is William Lewis. In addition to the planned sale of 2357 shares, he sold 4096 shares on 01/06/2026, and 10699 shares each on 12/18/2025 and 12/04/2025.

How many INSM shares did William Lewis sell in the past three months and for what proceeds?

Over the past three months, William Lewis sold 4096 shares for gross proceeds of 709959, and 10699 shares twice for gross proceeds of 1786437 and 2199583.

How were the 2357 INSM shares in the planned sale acquired?

The 2357 shares of INSM common stock to be sold were acquired on 01/05/2026 via Stock Plan Activity from the issuer.

What is the aggregate market value and shares outstanding referenced in this INSM filing?

For the planned sale of 2357 shares of common stock, the filing lists an aggregate market value of 412636 and 213273469 shares of common stock outstanding.

Which broker and exchange are involved in the INSM Rule 144 sale?

The planned sale of 2357 shares of INSM common stock will be executed through Merrill Lynch on the NASDAQ securities exchange.