<SEC-DOCUMENT>0001144204-12-040616.txt : 20120723
<SEC-HEADER>0001144204-12-040616.hdr.sgml : 20120723
<ACCEPTANCE-DATETIME>20120723184703
ACCESSION NUMBER:		0001144204-12-040616
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20120719
FILED AS OF DATE:		20120723
DATE AS OF CHANGE:		20120723

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Baker Brothers Life Sciences LP
		CENTRAL INDEX KEY:			0001363364
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14710
		FILM NUMBER:		12975321

	BUSINESS ADDRESS:	
		STREET 1:		667 MADISON AVENUE
		STREET 2:		21ST FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10065
		BUSINESS PHONE:		212-339-5633

	MAIL ADDRESS:	
		STREET 1:		667 MADISON AVENUE
		STREET 2:		21ST FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10065
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>form324683_20120723064645-.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2012-07-19</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001363364</rptOwnerCik>
            <rptOwnerName>Baker Brothers Life Sciences LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>667 MADISON AVENUE, 21ST FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>US 10065</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>13606093</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Common Stock Warrant (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>1.76</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>6608225</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F4"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The securities of Xoma Corporation reported herein are held directly by Baker Brothers Life Sciences, L.P. (&quot;Life Sciences&quot;), a limited partnership the sole general partner of which is Baker Brothers Life Sciences Capital, L.P., a limited partnership the sole general partner of which is Baker Brothers Life Sciences Capital (GP), LLC. Julian C. Baker and Felix J. Baker are the controlling members of Baker Brothers Life Sciences Capital (GP), LLC. Baker Bros. Advisors, LLC (the &quot;Adviser&quot;) serves as the Investment Adviser to Life Sciences. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest. On April 12, 2012, the Adviser, Life Sciences and the general partner of Life Sciences entered into an amended and restated management agreement which gave the Adviser complete and unlimited discretion and authority with respect to Life Sciences' investments and voting power over investments. The general partner of Life Sciences relinquished all discretion and authority with respect to Life Sciences' investments and voting power over investments. Julian C. Baker and Felix J. Baker each may be deemed to control the Adviser and to indirectly beneficially own the shares beneficially owned by it. Julian C. Baker and Felix J. Baker disclaim beneficial ownership of these securities, except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that Felix J. Baker or Julian C. Baker is the beneficial owner of the above referenced securities for purposes of Section 16 or for any other purpose. The shares reported herein have been previously reported by Felix J. Baker, Julian C. Baker and the Adviser in their own Section 16 reports. In the future, Life Sciences may jointly file Section 16 reports with Julian C. Baker, Felix J. Baker and the Adviser.</footnote>
        <footnote id="F2">Exercisable immediately</footnote>
        <footnote id="F3">Expiration date is five years from the date of Issuance</footnote>
        <footnote id="F4">Represents 13,216,449 warrant shares each of which is exercisable for .5 shares of the Issuer's common stock at an exercise price of $1.76 per share.</footnote>
    </footnotes>

    <remarks>Remarks:
Kelvin Neu, a Managing Director of Baker Bros. Advisors, LLC is a director of Xoma Corporation.  For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, Baker Brothers Life Sciences, L.P. is deemed a director by deputization by virtue of its representation on the Board of Directors of Xoma Corporation.</remarks>

    <ownerSignature>
        <signatureName>Baker Brothers Life Sciences, L.P., By: Baker Brothers Life Sciences Capital, L.P., its general partner, BY: Baker Brothers Life Sciences Capital (GP), LLC, its general partner, Name: Julian C. Baker Title: Managing Member /s/ Julian C. Baker</signatureName>
        <signatureDate>2012-07-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
