STOCK TITAN

Insmed (NASDAQ: INSM) CMO sells shares after option exercise filing

Filing Impact
(Very High)
Filing Sentiment
(Negative)
Form Type
4

Rhea-AI Filing Summary

Insmed Inc.'s Chief Medical Officer, Martina Flammer, M.D., reported a series of equity transactions in company stock. On January 6, 2026, she exercised a stock option for 8,570 shares of common stock at an exercise price of $26.43 per share, converting a derivative position into directly held stock. That same day, she reported open-market sales of common stock, including 4,783 shares at a weighted average price of $173.47, 2,830 shares at $174.21, and 957 shares at $175.01.

Additional sales included 1,615 shares at $173.33 on January 6, 1,434 shares at a weighted average of $175.84 on January 7, and on January 8, 1,660 shares at a weighted average of $173.87 and 3,251 shares at $174.17. A portion of the shares sold was specifically to satisfy tax withholding obligations upon vesting of restricted stock units and related broker fees. After these transactions, she directly held 86,794 shares of Insmed common stock. All trades noted as (1) were effected under a Rule 10b5-1 trading plan adopted on February 27, 2025.

Positive

  • None.

Negative

  • None.
Insider Flammer Martina M.D.
Role Chief Medical Officer
Sold 16,530 shs ($2.88M)
Type Security Shares Price Value
Sale Common Stock 1,660 $173.87 $289K
Sale Common Stock 3,251 $174.17 $566K
Sale Common Stock 1,434 $175.84 $252K
Exercise Stock Option (right to buy) 8,570 $0.00 --
Exercise Common Stock 8,570 $26.43 $227K
Sale Common Stock 4,783 $173.47 $830K
Sale Common Stock 2,830 $174.21 $493K
Sale Common Stock 957 $175.01 $167K
Sale Common Stock 1,615 $173.33 $280K
Holdings After Transaction: Common Stock — 90,045 shares (Direct); Stock Option (right to buy) — 0 shares (Direct)
Footnotes (1)
  1. This transaction was effected pursuant to a 10b5-1 trading plan adopted by the Reporting Person on February 27, 2025 in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended. This is the weighted average sales price representing 4,783 shares sold at prices ranging from $172.89 to $173.87 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. This is the weighted average sales price representing 2,830 shares sold at prices ranging from $173.92 to $174.80 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. This is the weighted average sales price representing 957 shares sold at prices ranging from $174.97 to $175.12 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. Shares sold to satisfy tax withholding obligations upon the vesting of Restricted Stock Units and to cover related broker fees. This is the weighted average sales price representing 1,434 shares sold at prices ranging from $175.72 to $176.00 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. This is the weighted average sales price representing 1,660 shares sold at prices ranging from $173.87 to $173.90 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request. The options became exercisable based on the following vesting schedule: 25% vested on the first anniversary of the grant date and an additional 12.5% vested on each sixth month anniversary date thereafter through the fourth anniversary of the date of grant.
SEC Form 4
FORM 4 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number: 3235-0287
Estimated average burden
hours per response: 0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
X
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
Flammer Martina M.D.

(Last) (First) (Middle)
700 US HIGHWAY 202/206

(Street)
BRIDGEWATER NJ 08807

(City) (State) (Zip)
2. Issuer Name and Ticker or Trading Symbol
INSMED Inc [ INSM ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director 10% Owner
X Officer (give title below) Other (specify below)
Chief Medical Officer
3. Date of Earliest Transaction (Month/Day/Year)
01/06/2026
4. If Amendment, Date of Original Filed (Month/Day/Year)
6. Individual or Joint/Group Filing (Check Applicable Line)
X Form filed by One Reporting Person
Form filed by More than One Reporting Person
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 01/06/2026 M(1) 8,570 A $26.43 103,324 D
Common Stock 01/06/2026 S(1) 4,783 D $173.47(2) 98,541 D
Common Stock 01/06/2026 S(1) 2,830 D $174.21(3) 95,711 D
Common Stock 01/06/2026 S(1) 957 D $175.01(4) 94,754 D
Common Stock 01/06/2026 S(5) 1,615 D $173.33 93,139 D
Common Stock 01/07/2026 S(5) 1,434 D $175.84(6) 91,705 D
Common Stock 01/08/2026 S(5) 1,660 D $173.87(7) 90,045 D
Common Stock 01/08/2026 S(1) 3,251 D $174.17 86,794 D
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year) 7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option (right to buy) $26.43 01/06/2026 M(1) 8,570 (8) 01/06/2032 Common Stock 8,570 $0 0 D
Explanation of Responses:
1. This transaction was effected pursuant to a 10b5-1 trading plan adopted by the Reporting Person on February 27, 2025 in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.
2. This is the weighted average sales price representing 4,783 shares sold at prices ranging from $172.89 to $173.87 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request.
3. This is the weighted average sales price representing 2,830 shares sold at prices ranging from $173.92 to $174.80 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request.
4. This is the weighted average sales price representing 957 shares sold at prices ranging from $174.97 to $175.12 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request.
5. Shares sold to satisfy tax withholding obligations upon the vesting of Restricted Stock Units and to cover related broker fees.
6. This is the weighted average sales price representing 1,434 shares sold at prices ranging from $175.72 to $176.00 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request.
7. This is the weighted average sales price representing 1,660 shares sold at prices ranging from $173.87 to $173.90 per share. The Reporting Person undertakes to provide to the SEC staff, the issuer, or a security holder of the issuer the number of shares sold at each price within the price range upon request.
8. The options became exercisable based on the following vesting schedule: 25% vested on the first anniversary of the grant date and an additional 12.5% vested on each sixth month anniversary date thereafter through the fourth anniversary of the date of grant.
Remarks:
/s/ Martina Flammer, M.D., by Michael A. Smith as Attorney-in-fact 01/08/2026
** Signature of Reporting Person Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transactions did Insmed (INSM) report for its Chief Medical Officer?

Insmed’s Chief Medical Officer, Martina Flammer, M.D., reported exercising a stock option for 8,570 shares of common stock at $26.43 per share and multiple open-market sales of Insmed common stock between January 6 and January 8, 2026, at weighted average prices generally between about $173 and $176 per share.

How many Insmed shares does the CMO hold after the reported Form 4 transactions?

After the reported transactions, Martina Flammer, M.D., directly owns 86,794 shares of Insmed common stock, as shown in the final line of the non-derivative holdings table.

Were the Insmed (INSM) CMO’s stock sales made under a Rule 10b5-1 trading plan?

Yes. A footnote states that the transactions marked with code M (1) and related sales were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 27, 2025 in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934.

What was the nature of the Insmed stock option exercised by the CMO?

The filing shows a stock option (right to buy) covering 8,570 shares of common stock with an exercise price of $26.43 per share. The options became exercisable with 25% vesting on the first anniversary of the grant date and an additional 12.5% vesting on each six-month anniversary thereafter through the fourth anniversary.

Were any of the Insmed CMO’s share sales made solely to cover tax obligations?

Yes. A footnote explains that certain shares were sold to satisfy tax withholding obligations upon the vesting of restricted stock units and to cover related broker fees.

How were the reported sale prices for Insmed (INSM) shares calculated in the Form 4?

Several reported sale prices are described as weighted average sales prices. For example, $173.47 represents 4,783 shares sold in the price range $172.89 to $173.87, and the reporting person undertakes to provide the specific number of shares sold at each price within the disclosed ranges upon request.