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).

1. Name and Address of Reporting Person* ROBERTS BRYAN E (Last) (First) (Middle) C/O VENROCK 3340 HILLVIEW AVE. (Street) PALO ALTO CA 94304 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol IRONWOOD PHARMACEUTICALS INC [ IRWD ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 06/06/2012
	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
Class A Common Stock	06/06/2012		C		15,000	A	(1)	15,187	D(2)
Class A Common Stock								1,654	I	By VR Management, LLC(3)
Class B Common Stock								40,000	I	By VR Management, LLC(3)
Class B Common Stock								2,559,605	I	By Venrock Associates(4)
Class B Common Stock								3,683,329	I	By Venrock Associates II, L.P.(5)
Class B Common Stock								48,387	I	By Venrock Entrepreneurs Fund, L.P.(6)
Class B Common Stock								2,017,021	I	By Venrock Healthcare Capital Partners, L.P.(7)
Class B Common Stock								382,979	I	By VHCP Co-Investment Holdings, LLC(8)

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
Class B Common Shares	(1)	06/06/2012		C			15,000	(1)	(1)	Class A Common Stock	15,000	$0	0	D

Explanation of Responses:

1. Each share of Class B Common Stock is convertible at any time at the option of the reporting person into one share of Class A Common Stock and has no expiration date. Each share of Class B Common Stock will convert automatically into one share of Class A Common Stock upon (i) any transfer, whether or not for value, (subject to certain exceptions); (ii) in the event of death of the reporting person; or (iii) the earliest of the following (A) the later of (1) the first date on which the number of shares of Class B Common Stock then outstanding represents less than 25% of the number of shares of Class B Common Stock outstanding at the closing of the Issuer's initial public offering, or (2) December 31, 2018, (B) December 31, 2038, or (C) the date agreed to in writing by the holders of at least a majority of then outstanding shares of Class B common stock.

2. The reporting person is a member of VR Management, LLC (the "Management Company"). Under an agreement between the reporting person and the Management Company, the reporting person is deemed to hold 187 of the reported shares for the sole benefit of the Management Company and must hold or sell these 187 shares solely upon the direction of the Management Company. The Management Company may be deemed the indirect beneficial owner of these 187 shares, and the reporting person may be deemed the indirect beneficial owner of these 187 shares through his interest in the Management Company. The reporting person disclaims beneficial ownership of these 187 shares except to the extent of his pecuniary interest therein.

3. Consists of shares held directly by the Management Company. The reporting person is a member of the Management Company and may be deemed to beneficially own these shares. The reporting person disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

4. Consists of shares held directly by Venrock Associates. The reporting person is a general partner of Venrock Associates and may be deemed to beneficially own these shares. The reporting person disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

5. Consists of shares held directly by Venrock Associates II, L.P. ("Venrock Associates II"). The reporting person is a general partner of Venrock Associates II and may be deemed to beneficially own these shares. The reporting person disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

6. Consists of shares held directly by Venrock Entrepreneurs Fund, L.P. ("Venrock Entrepreneurs"). Venrock Management, LLC ("Venrock Management") is the general partner of Venrock Entrepreneurs and may be deemed to beneficially own these shares. The reporting person is a member of Venrock Management and may be deemed to beneficially own these shares. The reporting person disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

7. Consists of shares held directly by Venrock Healthcare Capital Partners, L.P. ("VHCP LP"). VHCP Management, LLC ("VHCP Management") is the general partner of VHCP LP and may be deemed to beneficially own these shares. The reporting person is a member of VHCP Management and may be deemed to beneficially own these shares. The reporting person disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

8. Consists of shares held directly by VHCP Co-Investment Holdings, LLC ("VHCP Co-Investment"). VHCP Management is the manager of VHCP Co-Investment and may be deemed to beneficially own these shares. The reporting person is a member of VHCP Management and may be deemed to beneficially own these shares. The reporting person disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

Remarks:

	Bryan E. Roberts	06/08/2012
	** 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.