UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.     )

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o	Definitive Proxy Statement
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o	Soliciting Material under §240.14a-12
IRONWOOD PHARMACEUTICALS, INC.
(Name of Registrant as Specified In Its Charter)
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to Be Held on May 31, 2017. IRONWOOD PHARMACEUTICALS, INC. IRONWOOD PHARMACEUTICALS, INC. 301 BINNEY STREET CAMBRIDGE, MA 02142 Meeting Information Meeting Type: Annual Meeting For holders as of: April 7, 2017 Date: May 31, 2017 Time: 9:00 AM, Eastern Time Location: Ironwood Pharmaceuticals, Inc. 301 Binney Street Cambridge, MA 02142 You are receiving this communication because you hold shares in the company named above. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. E22600-P90680 See the reverse side of this notice to obtain proxy materials and voting instructions.

Before You Vote Proxy Materials Available to VIEW or RECEIVE: Proxy Materials Available to VIEW or RECEIVE: 1. NOTICE AND PROXY STATEMENT2. FORM 10-K How to View Online: Have the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (located on the following page) and visit: www.proxyvote .com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET:www.proxyvote.com 2) BY TELEPHONE: 1-800-579-1639 3) BY E-MAIL*:sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 17, 2017 to facilitate timely delivery. How To Vote Please Choose One of the Following Voting Methods Vote In Person: Many stockholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance and how to obtain directions to the meeting. At the meeting, you will need to request a ballot to vote these shares. Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (located on the following page) available and follow the instructions. E22601-P90680

Voting Items The Board of Directors recommends you vote FOR the following: 1.Election of Directors Nominees: 01) Andrew Dreyfus 02) Peter M. Hecht 03) Julie H. McHugh The Board of Directors recommends you vote FOR the following proposal: 2.Approval, by non-binding advisory vote, of the compensation paid to the named executive officers. The Board of Directors recommends you vote 1 year on the following proposal: 3.To recommend, by non-binding advisory vote, the frequency of future advisory votes on the compensation paid to the named executive officers. The Board of Directors recommends you vote FOR the following proposal: 4.Ratification of the selection of Ernst & Young LLP as the Company's independent registered public accounting firm for 2017. E22602-P90680

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