INSM (NASDAQ: INSM) insider plans new Form 144 sale after recent trades

Rhea-AI Filing Summary

A holder of common stock in a NASDAQ‑listed company has filed a Form 144 notice to sell 869 shares through Merrill Lynch, with an aggregate market value of $132,462. The filing states that 213,273,469 shares of this class were outstanding and lists an approximate sale date of February 5, 2026.

The securities to be sold were acquired on February 1, 2026 via stock plan activity from the issuer. The person filing, identified in recent sales as Martina Flammer, also sold multiple blocks of common shares between November 11, 2025 and February 3, 2026, with individual trades ranging from hundreds to tens of thousands of shares.

Insights

Equity analyst

Form 144 shows ongoing insider share sales but at a modest scale.

This Form 144 indicates that a shareholder intends to sell 869 common shares with an aggregate market value of $132,462. The shares were recently acquired through stock plan activity on February 1, 2026, suggesting routine equity compensation usage rather than a large standalone divestment.

The notice also lists prior sales by Martina Flammer from November 11, 2025 through February 3, 2026, including blocks such as 31,226 shares and 12,303 shares. While these represent meaningful personal transactions, the filing shows 213,273,469 shares outstanding, which implies these trades are small relative to the total share base.

The representation that the seller does not know any undisclosed material adverse information aligns with Rule 144 requirements and is standard in such notices. Future company filings will provide broader context on ownership changes and any effects from continued stock plan–related sales.

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	869	132462	213273469	02/05/2026	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			869	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
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	02/03/2026	795	123837
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	02/02/2026	7982	1233964
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/09/2026	1887	351332
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/08/2026	4911	854817
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/07/2026	1434	252154
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/06/2026	10185	1770153
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	01/05/2026	12303	2108459
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	12/01/2025	8895	1840841
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	11/11/2025	31226	5921820

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

What does the INSM Form 144 filing disclose about planned share sales?

The Form 144 filing discloses an intent to sell 869 common shares with an aggregate market value of $132,462. The shares are to be sold through Merrill Lynch on NASDAQ, with an approximate sale date of February 5, 2026.

Who is selling INSM shares and how were the shares acquired?

The notice shows sales for the account of Martina Flammer. The 869 shares covered by this Form 144 were acquired on February 1, 2026 via stock plan activity from the issuer, reflecting equity compensation rather than an open-market purchase.

How many INSM shares are outstanding compared with the Form 144 sale?

The filing reports 213,273,469 common shares outstanding. The planned sale of 869 shares under this Form 144 is therefore small relative to the total share base, providing context for the scale of this particular insider-related transaction.

What prior INSM share sales by Martina Flammer are disclosed?

The document lists multiple prior common stock sales by Martina Flammer from November 11, 2025 to February 3, 2026. Individual trades include 31,226 shares on November 11, 2025 and 12,303 shares on January 5, 2026, among other transactions.

On which exchange will the INSM Form 144 shares be sold and through which broker?

The Form 144 states that the 869 common shares are expected to be sold on the NASDAQ market. The broker handling the planned sale is Merrill Lynch, based at 1800 K Street NW, Suite 800, Washington, DC 20006.

What representation does the seller make in the INSM Form 144 filing?

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. This representation is part of the standard Rule 144 notice and is affirmed by signing the form.