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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001441848-10-000021.txt : 20100423
<SEC-HEADER>0001441848-10-000021.hdr.sgml : 20100423
<ACCEPTANCE-DATETIME>20100423134240
ACCESSION NUMBER:		0001441848-10-000021
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100421
FILED AS OF DATE:		20100423
DATE AS OF CHANGE:		20100423

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Llana Ted
		CENTRAL INDEX KEY:			0001453531

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34154
		FILM NUMBER:		10766773

	MAIL ADDRESS:	
		STREET 1:		1400 SEAPORT BOULEVARD
		CITY:			REDWOOD CITY
		STATE:			CA
		ZIP:			94063

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FACET BIOTECH CORP
		CENTRAL INDEX KEY:			0001441848
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				263070657
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1500 SEAPORT BLVD.
		CITY:			REDWOOD CITY
		STATE:			CA
		ZIP:			94063
		BUSINESS PHONE:		650-454-1000

	MAIL ADDRESS:	
		STREET 1:		1500 SEAPORT BLVD.
		CITY:			REDWOOD CITY
		STATE:			CA
		ZIP:			94063

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Biotech Spinco, Inc.
		DATE OF NAME CHANGE:	20080804
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-04-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001441848</issuerCik>
        <issuerName>FACET BIOTECH CORP</issuerName>
        <issuerTradingSymbol>FACT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001453531</rptOwnerCik>
            <rptOwnerName>Llana Ted</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O FACET BIOTECH CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>1500 SEAPORT BOULEVARD</rptOwnerStreet2>
            <rptOwnerCity>REDWOOD CITY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94063</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>DVP Comm'l &amp; Corp. Dev</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Comon Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-04-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>39893</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>27</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.17</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-04-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>64000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>27</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2016-01-23</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>64000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>9.95</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-04-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>26693</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>27</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2016-08-06</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>26693</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">This stock option was canceled and exchanged for a cash payment of $1,333,120.00 in accordance with the Agreement and Plan of Merger, dated March 9, 2010, among the issuer, Amber Acquisition Inc. and Abbott Laboratories in connection with the merger of Amber Acquisition Inc. with and into the issuer.  The cash payment made with respect to this stock option equals the product of (x) the number of option shares canceled multiplied by (y) the difference between the merger consideration ($27 per share) and the exercise price for this stock option.</footnote>
        <footnote id="F2">This stock option was canceled and exchanged for a cash payment of $455,115.65 in accordance with the Agreement and Plan of Merger, dated March 9, 2010, among the issuer, Amber Acquisition Inc. and Abbott Laboratories in connection with the merger of Amber Acquisition Inc. with and into the issuer.  The cash payment made with respect to this stock option equals the product of (x) the number of option shares canceled multiplied by (y) the difference between the merger consideration ($27 per share) and the exercise price for this stock option.</footnote>
        <footnote id="F3">This stock option was canceled and exchanged for a cash payment of $455,115.65 in accordance with the Agreement and Plan of Merger, dated March 9, 2010, among the issuer, Amber Acquisition Inc. and Abbott Laboratories in connection with the merger of Amber Acquisition Inc. with and into the issuer.  The cash payment made with respect to this stock option equals the product of (x) the number of option shares canceled multiplied by (y) the difference between the merger consideration ($27 per share) and the exercise price for this stock option.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Ted Llana</signatureName>
        <signatureDate>2010-04-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----