Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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 *
Whitten Timothy
  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)
President & CEO
(Last)
(First)
(Middle)
C/O INSMED INCORPORATED, 8720 STONY POINT PARKWAY, SUITE 200
3. Date of Earliest Transaction (Month/Day/Year)
01/31/2011
(Street)

RICHMOND, VA 23235
4. If Amendment, Date 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
(City)
(State)
(Zip)
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

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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 Underlying Securities
(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 of Derivative Security: 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 $ 0.59 01/31/2011   A   992,000   01/31/2012(1) 01/31/2021 Common Stock 992,000 $ 0.59 992,000 D  
Restricted Stock Units (2) 01/31/2011   A   1,302,000     (2)   (2) Common Stock (3) 1,302,000 (3) $ 0 2,294,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Whitten Timothy
C/O INSMED INCORPORATED
8720 STONY POINT PARKWAY, SUITE 200
RICHMOND, VA 23235
      President & CEO  

Signatures

 /s/ Timothy Whitten   02/01/2011
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) This Option shall be exercisable with respect to twenty-five percent (25%) of the shares of Common Stock subject to this Option on the first anniversary of the Date of Grant and with respect to an additional twelve and a half percent (12.5%) of the shares of Common Stock subject to this Option on the sixth month anniversary of the First Anniversary Date and each sixth month anniversary date thereafter through the fourth anniversary of the Date of Grant.
(2) Pursuant to the Management Agreement these awards are subject to both time (50% of the Award) and performance-based (50% of the Award) vesting. The portion of the Award subject to time-based vesting shall vest on the 3rd anniversary of the grant date or January 31, 2014, so long as the member of management continues to be employed by the Company. The portion of the Award subject to performance-based vesting shall vest based on the date on which the Board determines that Arikace has achieved its primary endpoint in a Phase III trial, provided that the Grantee continues to be employed with the Company on such date.
(3) Restricted Stock Units will be paid to the grantee in cash upon vesting, unless one of the following occurs: 1) the shareholders of the issuer approve an amendment to the issuer's Amended & Restated 2000 Stock Incentive Plan to increase the number of shares of common stock that may be issued under the plan or 2) additional shares become available to the plan through stock option expirations and/or employee terminations, in which case the grantee may receive shares of common stock in lieu of cash.

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