<SEC-DOCUMENT>0000791908-16-000174.txt : 20161103
<SEC-HEADER>0000791908-16-000174.hdr.sgml : 20161103
<ACCEPTANCE-DATETIME>20161103193817
ACCESSION NUMBER:		0000791908-16-000174
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20161101
FILED AS OF DATE:		20161103
DATE AS OF CHANGE:		20161103

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:			BERKELEY
		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:			Neal James R
		CENTRAL INDEX KEY:			0001600865

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14710
		FILM NUMBER:		161973345

	MAIL ADDRESS:	
		STREET 1:		2910 SEVENTH STREET
		CITY:			BERKELEY
		STATE:			CA
		ZIP:			94710
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-11-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001600865</rptOwnerCik>
            <rptOwnerName>Neal James R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2910 SEVENTH STREET</rptOwnerStreet1>
            <rptOwnerStreet2></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>VP Business Development</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2016-11-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>150</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>5.25</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20541</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>659</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by 401(k)</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 12, 2016.</footnote>
        <footnote id="F2">The shares and price represented reflect a 1:20 reverse split effective 10/18/2016.</footnote>
        <footnote id="F3">Includes unvested RSUs reported on Table 1.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Denis Quinlan For: James R. Neal</signatureName>
        <signatureDate>2016-11-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>poa.txt
<TEXT>
Exhibit 24
POWER OF ATTORNEY


        I appoint each of John Varian, Thomas Bums, Denis Quinlan and
Diane Wilcock, signing singly, as my attorneys-in-fact to:

1) 	prepare, execute in my name and on my behalf, and submit to
the U.S. Securities and Exchange Commission ("SEC")  a Form ID,
including amendments, and any other documents necessary to obtain
codes and passwords enabling me to make electronic filings with the
SEC of reports required by Section 16(a) of the Securities Exchange
Act of 1934, as amended ("Exchange Act"), or any rule or regulation
of the SEC;

2) 	execute on my behalf Forms 3, 4 or 5 and any amendments under
Section 16 of the Exchange Act, and its rules and regulations;

3) 	perform all acts on my behalf which may be necessary to
complete the execution and filing of any such Form 3, 4 or 5 with
the SEC and any other authority; and

4) 	take any other action in connection with the above which, in
the opinion of such attorney-in-fact, may be of benefit to me, in my
best interest of, or legally required of me, it being understood
that the documents executed by such attorneys-in-fact on my behalf
under this Power of Attorney shall be in such form and shall contain
such terms and conditions as such attorneys-in-fact may approve in
their sole discretion.



       I grant to each attorney-in-fact full power and authority to perform
every act necessary in the exercise of any of the rights and powers
granted, as fully as I might do if personally present, with full power of
substitution or revocation, ratifying and confirming all that such
attorneys-in? fact, or their substitutes, shall lawfully do or cause to be
done by virtue of this power of attorney and the rights and powers
granted.  I acknowledge that the above attorneys-in-fact, in serving in
such capacity at my request, are not assuming any of my responsibilities
to comply with Section
16 of the Exchange Act.

	This power of attorney shall remain in effect until I am no longer
required to file Forms 3, 4 and 5 with respect to my holdings of and
transactions in securities issued by XOMA Corporation or its subsidiaries or
successors, unless earlier revoked by me in a signed writing delivered to the
above attorneys-in-fact.


//James R. Neal//

____________________________________
James R. Neal
October.24.2016 	 Date
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
