INSM insider plans sale of 27,173 shares

Reporting person Martina Flammer has filed to sell up to 27,173 shares of common stock, to be executed through Merrill Lynch, with an approximate sale date of 08/06/2026.

Rhea-AI Filing Summary

Reporting person Martina Flammer has filed to sell up to 27,173 shares of common stock, to be executed through Merrill Lynch, with an approximate sale date of 08/06/2026. The issuer reports 218,381,503 shares outstanding as of that date.

The sale relates to stock plan activity. Over the past three months, Flammer has reported several open-market sales of common shares between May and July 2026, each disclosing the number of shares and corresponding dollar amounts.

Key Figures

Planned shares to be sold: 27,173 shares Shares outstanding: 218,381,503 shares Planned sale date: 08/06/2026 +5 more

8 metrics

Planned shares to be sold 27,173 shares Common stock planned sale in connection with stock plan activity

Shares outstanding 218,381,503 shares Common stock outstanding as of 08/06/2026

Planned sale date 08/06/2026 Approximate date for sale of 27,173 common shares

Sale on 07/06/2026 12,302 shares; 1,352,864 Common stock sold by Martina Flammer during past three months

Sale on 06/05/2026 1,858 shares; 192,811 Common stock sold by Martina Flammer during past three months

Sale on 06/03/2026 2,566 shares; 262,418 Common stock sold by Martina Flammer during past three months

Sale on 05/14/2026 10,479 shares; 1,231,599 Common stock sold by Martina Flammer during past three months

Sale on 05/13/2026 7,854 shares; 897,137 Common stock sold by Martina Flammer during past three months

Key Terms

Form 144, Stock Plan Activity, securities to be sold, aggregate market value

4 terms

Form 144 regulatory

"144: Securities Sold During The Past 3 Months"

Form 144 is a document that investors must file with the government when they plan to sell a large number of shares of a company's stock. It helps ensure transparency so everyone knows how many shares are being sold and when, which can impact the stock's price.

Stock Plan Activity financial

"Common | 08/06/2026 | Stock Plan Activity | Issuer"

securities to be sold regulatory

"144: Securities To Be Sold"

aggregate market value financial

"Common | Merrill Lynch ... | 27173 | 3494755 | 218381503"

Aggregate market value is the combined price you would pay to buy all outstanding shares of a company or all companies in a group at current market prices — essentially the sum of each stock’s market capitalization. It matters to investors because it shows the overall size and weight of an investment or sector (like the total cost to buy every piece of a puzzle), helps compare scale across companies or markets, and influences index composition and risk exposure.

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

What share sale is reported for INSM in this Form 144 filing?

The filing reports that 27,173 shares of common stock are planned to be sold by reporting person Martina Flammer in connection with stock plan activity, with an approximate sale date of 08/06/2026 through Merrill Lynch.

How many INSM shares are outstanding according to this Form 144?

The issuer lists 218,381,503 shares of common stock outstanding as of 08/06/2026. This figure provides a baseline for understanding the scale of the 27,173-share planned sale relative to total shares.

Who is the reporting person in the INSM Form 144 filing?

The reporting person is Martina Flammer, whose address is given as 700 US Highway 202/206, Bridgewater, NJ 08807. She reports planned sales and prior three-month sales of the issuer’s common stock.

What broker is listed for the planned INSM share sale?

The broker listed is Merrill Lynch, located at 1800 K St NW, Suite 800, Washington, DC 20006. Merrill Lynch is identified in connection with the planned sale of 27,173 common shares on or after 08/06/2026.

What prior INSM stock sales by the reporting person are disclosed?

Disclosed prior sales include 12,302 shares on 07/06/2026, 1,858 shares on 06/05/2026, 2,566 shares on 06/03/2026, plus additional sales in May 2026, each with corresponding dollar amounts reported.

On which market is the INSM common stock listed in this filing?

The common stock referenced in the filing is listed on the NASDAQ market. The Form 144 ties the planned sale of 27,173 shares and past sales to this NASDAQ-listed class of common stock.

AI-generated analysis. How Rhea-AI works. Not financial advice.

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Available on EDGAR 08/06/2026 - 04:10 PM Accepted by SEC EDGAR 08/06/2026 - 04:09 PM Learn about SEC filing dates

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	0001796960
Filer CCC	XXXXXXXX
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer	INSMED INCORPORATED
SEC File Number
Address of Issuer	700 US Highway 202/206 Bridgewater NEW JERSEY 08807
Phone	9089779900
Name of Person for Whose Account the Securities are To Be Sold	Martina Flammer
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	Officer

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	27173	3494755	218381503	08/06/2026	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	08/06/2026	Stock Plan Activity	Issuer			27173	08/06/2026	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	07/06/2026	12302	1352864
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	06/05/2026	1858	192811
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	06/03/2026	2566	262418
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	05/14/2026	10479	1231599
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	05/13/2026	7854	897137
Martina Flammer 700 US Highway 202/206 Bridgewater NJ 08807	Common	05/11/2026	12949	1300105

144: Remarks and Signature

Remarks
Date of Notice	08/06/2026
Date of Plan Adoption or Giving of Instruction, If Relying on Rule 10b5-1	02/27/2025
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	Martina Flammer
ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)