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 *
Currie Mark G
  2. Issuer Name and Ticker or Trading Symbol
IRONWOOD PHARMACEUTICALS INC [IRWD]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Scientific Officer
(Last)
(First)
(Middle)
C/O IRONWOOD PHARMACEUTICALS, INC., 301 BINNEY STREET
3. Date of Earliest Transaction (Month/Day/Year)
04/11/2011
(Street)

CAMBRIDGE, MA 02142
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
Class B Common Stock 04/11/2011   M   600 A $ 0.6 210,600 D  
Class B Common Stock 04/11/2011   S(1)   600 D $ 15 210,000 D  
Class B Common Stock 04/13/2011   M   24,263 A $ 0.6 234,263 D  
Class B Common Stock 04/13/2011   S(1)   24,263 D $ 15 210,000 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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
Employee Stock Option (Right to Buy) $ 0.6 04/11/2011   M     600   (2) 09/24/2012 Class B Common Stock 600 $ 0 59,400 D  
Employee Stock Option (Right to Buy) $ 0.6 04/13/2011   M     24,263   (2) 09/24/2012 Class B Common Stock 24,263 $ 0 35,137 D  
Employee Stock Option (Right to Buy) (3) $ 3.76               (4) 01/31/2018(3) Class B Common Stock 120,000   120,000 D  
Employee Stock Option (Right to Buy) (5) $ 4.89               (6) 02/11/2019(5) Class B Common Stock 125,000   125,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Currie Mark G
C/O IRONWOOD PHARMACEUTICALS, INC.
301 BINNEY STREET
CAMBRIDGE, MA 02142
      Chief Scientific Officer  

Signatures

 /a/ Halley E. Gilbert Attorney-in-Fact   04/13/2011
**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 sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person. In order to effect the sale, these shares of Class B Common Stock were converted into shares of Class A Common Stock in accordance with the issuer's certificate of incorporation.
(2) The option vested as to 25% of the shares of Class B Common Stock on the first anniversary of August 22, 2002, and 1/48th of the shares of Class B Common Stock vested each month thereafter for the next 36 months. The option was fully vested as of August 22, 2006.
(3) The expiration date of the option, as reported in the reporting person's Form 3 filed on February 2, 2010, contained a typographical error. The correct expiration date is January 31, 2018.
(4) The option vests as to 1.25% of the shares of Class B Common Stock on each monthly anniversary of January 1, 2008 for the first 36 months, and vests as to 4.5833% of the shares of Class B Common Stock on each monthly anniversary thereafter. The option is subject to an early exercise provision and is immediately exercisable.
(5) The expiration date of the option, as reported in the reporting person's Form 3 filed on February 2, 2010, contained a typographical error. The correct expiration date is February 11, 2019.
(6) The option vests as to 1.25% of the shares of Class B Common Stock on each monthly anniversary of January 1, 2009 for the first 36 months, and vests as to 4.5833% of the shares of Class B Common Stock on each monthly anniversary thereafter. The option is subject to an early exercise provision and is immediately exercisable.

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