<SEC-DOCUMENT>0001037389-24-000096.txt : 20241113
<SEC-HEADER>0001037389-24-000096.hdr.sgml : 20241113
<ACCEPTANCE-DATETIME>20241113144153
ACCESSION NUMBER:		0001037389-24-000096
CONFORMED SUBMISSION TYPE:	SCHEDULE 13G
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20241113

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IRONWOOD PHARMACEUTICALS INC
		CENTRAL INDEX KEY:			0001446847
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		IRS NUMBER:				043404176
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SCHEDULE 13G
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-85292
		FILM NUMBER:		241453324

	BUSINESS ADDRESS:	
		STREET 1:		100 SUMMER STREET, SUITE 2300
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
		BUSINESS PHONE:		617-621-7722

	MAIL ADDRESS:	
		STREET 1:		100 SUMMER STREET, SUITE 2300
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			RENAISSANCE TECHNOLOGIES LLC
		CENTRAL INDEX KEY:			0001037389
		ORGANIZATION NAME:           	
		IRS NUMBER:				260385758
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SCHEDULE 13G

	BUSINESS ADDRESS:	
		STREET 1:		800 THIRD AVE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		2124866780

	MAIL ADDRESS:	
		STREET 1:		800 THIRD AVE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	RENAISSANCE TECHNOLOGIES CORP
		DATE OF NAME CHANGE:	19990324
</SEC-HEADER>
<DOCUMENT>
<TYPE>SCHEDULE 13G
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/schedule13g" xmlns:com="http://www.sec.gov/edgar/common">
    <headerData>
        <submissionType>SCHEDULE 13G</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001037389</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <coverPageHeader>
            <securitiesClassTitle>Class A common stock, $0.001 par value per share</securitiesClassTitle>
            <eventDateRequiresFilingThisStatement>05/15/2024</eventDateRequiresFilingThisStatement>
            <issuerInfo>
                <issuerCik>0001446847</issuerCik>
                <issuerName>IRONWOOD PHARMACEUTICALS INC</issuerName>
                <issuerCusip>46333X108</issuerCusip>
                <issuerPrincipalExecutiveOfficeAddress>
                    <com:street1>100 SUMMER STREET, SUITE 2300</com:street1>
                    <com:city>BOSTON</com:city>
                    <com:stateOrCountry>MA</com:stateOrCountry>
                    <com:zipCode>02110</com:zipCode>
                </issuerPrincipalExecutiveOfficeAddress>
            </issuerInfo>
            <designateRulesPursuantThisScheduleFiled>
                <designateRulePursuantThisScheduleFiled>Rule 13d-1(b)</designateRulePursuantThisScheduleFiled>
            </designateRulesPursuantThisScheduleFiled>
        </coverPageHeader>
        <coverPageHeaderReportingPersonDetails>

            <reportingPersonName>Renaissance Technologies LLC</reportingPersonName>
            <citizenshipOrOrganization>DE</citizenshipOrOrganization>
            <reportingPersonBeneficiallyOwnedNumberOfShares>
                <soleVotingPower>8597198</soleVotingPower>
                <sharedVotingPower>0</sharedVotingPower>
                <soleDispositivePower>8597198</soleDispositivePower>
                <sharedDispositivePower>0</sharedDispositivePower>
            </reportingPersonBeneficiallyOwnedNumberOfShares>
            <reportingPersonBeneficiallyOwnedAggregateNumberOfShares>8597198</reportingPersonBeneficiallyOwnedAggregateNumberOfShares>
            <classPercent>5.37</classPercent>
            <typeOfReportingPerson>IA</typeOfReportingPerson>
        </coverPageHeaderReportingPersonDetails>
        <coverPageHeaderReportingPersonDetails>
            <reportingPersonName>Renaissance Technologies Holdings Corporation</reportingPersonName>
            <citizenshipOrOrganization>DE</citizenshipOrOrganization>
            <reportingPersonBeneficiallyOwnedNumberOfShares>
                <soleVotingPower>8597198</soleVotingPower>
                <sharedVotingPower>0</sharedVotingPower>
                <soleDispositivePower>8597198</soleDispositivePower>
                <sharedDispositivePower>0</sharedDispositivePower>
            </reportingPersonBeneficiallyOwnedNumberOfShares>
            <reportingPersonBeneficiallyOwnedAggregateNumberOfShares>8597198</reportingPersonBeneficiallyOwnedAggregateNumberOfShares>
            <classPercent>5.37</classPercent>
            <typeOfReportingPerson>HC</typeOfReportingPerson>
        </coverPageHeaderReportingPersonDetails>
        <items>
            <item1>
                <issuerName>IRONWOOD PHARMACEUTICALS INC</issuerName>
                <issuerPrincipalExecutiveOfficeAddress>100 SUMMER STREET, SUITE 2300, BOSTON, MA 02110</issuerPrincipalExecutiveOfficeAddress>
            </item1>
            <item2>
                <filingPersonName>This Schedule 13G is being filed by Renaissance Technologies LLC ("RTC") and Renaissance Technologies Holdings Corporation ("RTHC").</filingPersonName>
                <principalBusinessOfficeOrResidenceAddress>800 Third Avenue New York, New York 10022</principalBusinessOfficeOrResidenceAddress>
                <citizenship>RTC is a Delaware limited liability company, and RTHC is a Delaware corporation.</citizenship>
            </item2>
            <item3>
                <notApplicableFlag>N</notApplicableFlag>
                <typeOfPersonFiling>IA</typeOfPersonFiling>
            </item3>
            <item4>
                <amountBeneficiallyOwned>8597198</amountBeneficiallyOwned>
                <classPercent>5.37</classPercent>
                <numberOfSharesPersonHas>
                    <solePowerOrDirectToVote>8597198</solePowerOrDirectToVote>
                    <sharedPowerOrDirectToVote>0</sharedPowerOrDirectToVote>
                    <solePowerOrDirectToDispose>8597198</solePowerOrDirectToDispose>
                    <sharedPowerOrDirectToDispose>0</sharedPowerOrDirectToDispose>
                </numberOfSharesPersonHas>
            </item4>
            <item5>
                <notApplicableFlag>Y</notApplicableFlag>
                <classOwnership5PercentOrLess>N</classOwnership5PercentOrLess>
            </item5>
            <item6>
                <notApplicableFlag>N</notApplicableFlag>
                <ownershipMoreThan5PercentOnBehalfOfAnotherPerson>Certain funds managed by RTC have the right to receive dividends and proceeds from the sale of the securities which are the subject of this report.</ownershipMoreThan5PercentOnBehalfOfAnotherPerson>
            </item6>
            <item7>
                <notApplicableFlag>Y</notApplicableFlag>
            </item7>
            <item8>
                <notApplicableFlag>Y</notApplicableFlag>
            </item8>
            <item9>
                <notApplicableFlag>Y</notApplicableFlag>
            </item9>
            <item10>
                <notApplicableFlag>N</notApplicableFlag>
                <certifications>By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.</certifications>
            </item10>
        </items>
        <exhibitInfo>In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, each of the undersigned agrees to the filing on behalf of each of a Statement on Schedule 13G, and all amendments thereto, with respect to the Class A common stock, $0.001 par value per share of IRONWOOD PHARMACEUTICALS INC.</exhibitInfo>
        <signatureInformation>
            <reportingPersonName>Renaissance Technologies LLC</reportingPersonName>
            <signatureDetails>
                <signature>Brian Felczak</signature>
                <title>Chief Financial Officer</title>
                <date>11/13/2024</date>
            </signatureDetails>
        </signatureInformation>
        <signatureInformation>
            <reportingPersonName>Renaissance Technologies Holdings Corporation</reportingPersonName>
            <signatureDetails>
                <signature>Brian Felczak</signature>
                <title>Vice President</title>
                <date>11/13/2024</date>
            </signatureDetails>
        </signatureInformation>
    </formData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
