<SEC-DOCUMENT>0001438588-12-000044.txt : 20121001
<SEC-HEADER>0001438588-12-000044.hdr.sgml : 20121001
<ACCEPTANCE-DATETIME>20121001180237
ACCESSION NUMBER:		0001438588-12-000044
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20120928
FILED AS OF DATE:		20121001
DATE AS OF CHANGE:		20121001

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RUBIN PAUL D
		CENTRAL INDEX KEY:			0001210905

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14710
		FILM NUMBER:		121121039

	MAIL ADDRESS:	
		STREET 1:		37 GREYSTONE LANE
		CITY:			SUDBURY
		STATE:			MA
		ZIP:			01776

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			XOMA Corp
		CENTRAL INDEX KEY:			0000791908
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				942756657
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2910 SEVENTH ST
		CITY:			BERKELEY
		STATE:			CA
		ZIP:			94710
		BUSINESS PHONE:		5106441170

	MAIL ADDRESS:	
		STREET 1:		2910 SEVENTH ST
		CITY:			BERKLEY
		STATE:			CA
		ZIP:			94710

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	XOMA LTD /DE/
		DATE OF NAME CHANGE:	19990107

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	XOMA CORP /DE/
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-09-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000791908</issuerCik>
        <issuerName>XOMA Corp</issuerName>
        <issuerTradingSymbol>XOMA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001210905</rptOwnerCik>
            <rptOwnerName>RUBIN PAUL D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O XOMA CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>2910 SEVENTH STREET</rptOwnerStreet2>
            <rptOwnerCity>BERKELEY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94710</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. VP Clinical Dev. &amp; CMO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2012-09-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>542</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.5055</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1203</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2208</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by 401(k)</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares acquired through the XOMA Ltd. 1998 Employee Share Purchase Plan (Amended and Restated through May 26, 2011).  Exempt transaction under Rule 16b-3(c).</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Fred Kurland  For: Paul Rubin</signatureName>
        <signatureDate>2012-09-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
