# EDGAR Filing Document

**Accession Number:** 0001104506
**File Stem:** 0001796960-26-000002
**Filing Date:** 2026-1
**Character Count:** 10409
**Document Hash:** 7ff4451d4271be29183ba5a8448c4093
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001796960-26-000002.hdr.sgml**: 20260106

**ACCESSION NUMBER**: 0001796960-26-000002

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260102

**FILED AS OF DATE**: 20260106

**DATE AS OF CHANGE**: 20260106

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Flammer Martina M.D.
- **CENTRAL INDEX KEY:** 0001796960

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 000-30739
- **FILM NUMBER:** 26511460

**MAIL ADDRESS:**
- **STREET 1:** 700 US HIGHWAY 202/206
- **CITY:** BRIDGEWATER
- **STATE:** NJ
- **ZIP:** 08807
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** INSMED Inc
- **CENTRAL INDEX KEY:** 0001104506
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 541972729
- **STATE OF INCORPORATION:** VA
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 700 US HIGHWAY 202/206
- **CITY:** BRIDGEWATER
- **STATE:** NJ
- **ZIP:** 08807
- **BUSINESS PHONE:** 908-977-9900

**MAIL ADDRESS:**
- **STREET 1:** 700 US HIGHWAY 202/206
- **CITY:** BRIDGEWATER
- **STATE:** NJ
- **ZIP:** 08807

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** INSMED INC
- **DATE OF NAME CHANGE:** 20000128

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] 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**<sup>*</sup><br>Flammer Martina M.D.<br><sub>(Last) (First) (Middle)</sub><br>700 US HIGHWAY 202/206<br><sub>(Street)</sub><br>BRIDGEWATER, NJ 08807<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-01-02 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [ ] 10% Owner<br>[X] Officer (give title below) [ ] Other (specify below)<br>_Chief Medical Officer_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>INSMED Inc [ INSM ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock | 2026-01-02 |  | A |  | 5998<sup>(1)</sup> | A | <sup>(2)</sup> | 89109 | D |  |
| Common Stock | 2026-01-02 |  | A |  | 5645<sup>(3)</sup> | A | <sup>(2)</sup> | 94754 | D |  |
| Common Stock | 2026-01-05 |  | M<sup>(4)</sup> |  | 4358 | A | $19.74 | 99112 | D |  |
| Common Stock | 2026-01-05 |  | M<sup>(4)</sup> |  | 7945 | A | $29.13 | 107057 | D |  |
| Common Stock | 2026-01-05 |  | S<sup>(4)</sup> |  | 2799 | D | 169.29<sup>(5)</sup> | 104258 | D |  |
| Common Stock | 2026-01-05 |  | S<sup>(4)</sup> |  | 3205 | D | 170.61<sup>(6)</sup> | 101053 | D |  |
| Common Stock | 2026-01-05 |  | S<sup>(4)</sup> |  | 2836 | D | 171.19<sup>(7)</sup> | 98217 | D |  |
| Common Stock | 2026-01-05 |  | S<sup>(4)</sup> |  | 286 | D | $171.92 | 97931 | D |  |
| Common Stock | 2026-01-05 |  | S<sup>(4)</sup> |  | 1820 | D | 173.45<sup>(8)</sup> | 96111 | D |  |
| Common Stock | 2026-01-05 |  | S<sup>(4)</sup> |  | 655 | D | 174.28<sup>(9)</sup> | 95456 | D |  |
| Common Stock | 2026-01-05 |  | S<sup>(4)</sup> |  | 702 | D | 175.73<sup>(10)</sup> | 94754 | D |  |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| Stock Option (right to buy) | $177.12 | 2026-01-02 |  | A |  | 31280 |  | <sup>(11)</sup> | 2036-01-02 | Common Stock | 31280 | $0 | 31280 | D |  |
| Stock Option (right to buy) | $19.74 | 2026-01-05 |  | M<sup>(4)</sup> |  |  | 4358 | <sup>(12)</sup> | 2033-01-05 | Common Stock | 4358 | $0 | 8715 | D |  |
| Stock Option (right to buy) | $29.13 | 2026-01-05 |  | M<sup>(4)</sup> |  |  | 7945 | <sup>(12)</sup> | 2034-01-04 | Common Stock | 7945 | $0 | 31780 | D |  |

---

### Footnotes:

(1) Represents Restricted Stock Units (RSUs), each representing a contingent right to receive one share of Common Stock, granted pursuant to the Company's Amended and Restated 2019 Incentive Plan, as amended. The RSUs vest as follows: 25% on the first day of the first month following the first anniversary of the date of grant (the Initial Vesting Date) and  25% on each anniversary of the Initial Vesting Date until fully vested.

(2) Each RSU was granted on January 2, 2026 for no consideration.

(3) Represents RSUs, each representing a contingent right to receive one share of Common Stock, granted pursuant to the Company's Amended and Restated 2019 Incentive Plan, as amended. The RSUs vest in full on February 1, 2029.

(4) 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.

(5) This is the weighted average sales price representing 2,799 shares sold at prices ranging from $168.88 to $169.69 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.

(6) This is the weighted average sales price representing 3,205 shares sold at prices ranging from $169.91 to $170.90 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.

(7) This is the weighted average sales price representing 2,836 shares sold at prices ranging from $170.91 to $171.89 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) This is the weighted average sales price representing 1,820 shares sold at prices ranging from $173.05 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.

(9) This is the weighted average sales price representing 655 shares sold at prices ranging from $174.20 to $174.43 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.

(10) This is the weighted average sales price representing 702 shares sold at prices ranging from $175.54 to $176.12 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.

(11) These stock options were granted under the Company's Amended and Restated 2019 Incentive Plan, as amended. The options become exercisable based on the following vesting schedule: 25% vest on the Initial Vesting Date and an additional 12.5% vest every six months thereafter until fully vested.

(12) The options become exercisable based on the following vesting schedule: 25% vest on the first anniversary of the grant date and an additional 12.5% vest on each sixth month anniversary date thereafter through the fourth anniversary of the date of grant.

**Signature:** /s/ Martina Flammer, M.D., by Michael A. Smith as Attorney-in-fact  
**Date:** 2026-01-06

### Remarks:

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.**