William Lewis to sell 3,009 INSM (NASDAQ: INSM) shares under Rule 144

Rhea-AI Filing Summary

William Lewis filed a notice of proposed sale under Rule 144 to sell 3,009 shares of common stock through Merrill Lynch in Washington, DC. The shares are listed on NASDAQ, and the approximate sale date stated is February 3, 2026.

The shares to be sold were acquired on February 1, 2026 via stock plan activity from the issuer. Over the prior three months, William Lewis reported several other common stock sales, including blocks of 19,215 and 10,699 shares, with disclosed gross proceeds for each transaction.

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	3009	470412	213273469	02/03/2026	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	02/01/2026	Stock Plan Activity	Issuer			3009	02/01/2026	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	01/20/2026	10699	1700420
William Lewis 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/12/2026	19215	3247325
William Lewis 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/08/2026	3223	561349
William Lewis 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/07/2026	2357	412639
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 does the INSM Form 144 filing by William Lewis disclose?

The filing discloses that William Lewis plans to sell 3,009 shares of common stock under Rule 144. The shares will be sold through Merrill Lynch on NASDAQ, with an approximate sale date of February 3, 2026 and stated aggregate market value information.

How many INSM shares is William Lewis proposing to sell in this notice?

William Lewis is proposing to sell 3,009 shares of common stock. These shares are to be sold through Merrill Lynch, with the securities listed on NASDAQ, and the notice specifies an approximate sale date of February 3, 2026 for the planned transaction.

How and when did William Lewis acquire the INSM shares being sold?

The 3,009 shares to be sold were acquired on February 1, 2026 through stock plan activity from the issuer. The filing classifies the acquisition as common stock, notes the issuer as the source, and indicates the same date as the date of payment with non-cash consideration marked as not applicable.

What prior INSM stock sales has William Lewis reported in the last three months?

The notice lists multiple prior common stock sales over the last three months, including blocks of 10,699, 19,215, 4,096, and other amounts. Each transaction entry includes the sale date, number of shares sold, and reported gross proceeds for that specific sale.

Which broker and exchange are involved in William Lewis’s planned INSM share sale?

The planned sale of 3,009 common shares is to be executed through Merrill Lynch, located at 1800 K Street NW, Suite 800, Washington, DC 20006. The filing identifies NASDAQ as the securities exchange where the common stock is traded and intended to be sold.

What representation does the seller make about non-public information in this INSM Form 144?

By signing the notice, the seller represents that they do not know any material adverse information about the issuer’s current or prospective operations that has not been publicly disclosed. The form also warns that intentional misstatements or omissions can constitute federal criminal violations.