FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person *   FMR LLC 2. Date of Event Requiring Statement (Month/Day/Year) 10/25/2012 3. Issuer Name and Ticker or Trading Symbol INSMED INC [INSM] (Last) (First) (Middle) 82 DEVONSHIRE STREET 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director __X__ 10% Owner _____ Officer (give title below) __X__ Other (specify below) Edward C. Johnson 3d 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) BOSTON, MA 02109 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Common Stock 1,869,084 I By Beacon Bioventures LP (1) Common Stock 12,668 I By Beacon Bioventures Principals LP (1)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
FMR LLC 82 DEVONSHIRE STREET BOSTON, MA 02109	Â	  X	Â	Edward C. Johnson 3d

Signatures

Scott C. Goebel, Duly authorized under Powers of Attorney effective as of June 1, 2008, by and on behalf of FMR LLC and its direct and indirect subsidiaries and by and on behalf of Edward C. Johnson 3d.		11/01/2012
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(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).
(1)	Column 2 does not include shares beneficially owned by Fidelity Management & Research Company as a result of acting as investment adviser to various investment companies as disclosed in Remark 1 below.
  Remarks: Remark 1:  In addition to the securities shown in Table 1, Fidelity Management & Research Company, a wholly owned subsidiary of FMR LLC and an investment adviser registered under the Investment Advisers Act of 1940, is the beneficial owner of 1,457,800 shares, or 4.6755%, of Common Stock of Insmed Inc. as a result of acting as investment adviser to various investment companies registered under the Investment Company Act of 1940. FMR LLC and Edward C. Johnson 3d have no pecuniary interest in the 1,457,800 shares of Common Stock.

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