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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>0001179110-09-001407.txt : 20090122
<SEC-HEADER>0001179110-09-001407.hdr.sgml : 20090122
<ACCEPTANCE-DATETIME>20090122162103
ACCESSION NUMBER:		0001179110-09-001407
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090114
FILED AS OF DATE:		20090122
DATE AS OF CHANGE:		20090122

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PACWEST BANCORP
		CENTRAL INDEX KEY:			0001102112
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		IRS NUMBER:				330885320
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6110 EL TORDO
		CITY:			RANCHO SANTA FE
		STATE:			CA
		ZIP:			92067
		BUSINESS PHONE:		8587563023

	MAIL ADDRESS:	
		STREET 1:		275 NORTH BREA BLVD
		CITY:			BREA
		STATE:			CA
		ZIP:			92821

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIRST COMMUNITY BANCORP /CA/
		DATE OF NAME CHANGE:	19991229

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROSE JOHN W
		CENTRAL INDEX KEY:			0001091449
		STATE OF INCORPORATION:			FL
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30747
		FILM NUMBER:		09539455

	BUSINESS ADDRESS:	
		STREET 1:		13245 ATLANTIC BLVD SUITE 5
		CITY:			JACKSONVILLE
		STATE:			FL
		ZIP:			32225
		BUSINESS PHONE:		9044213051

	MAIL ADDRESS:	
		STREET 1:		100 NORTH LAURA STREET, SUITE 1000
		CITY:			JACKSONVILLE
		STATE:			FL
		ZIP:			32202
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 3 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0203</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2009-01-14</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001102112</issuerCik>
        <issuerName>PACWEST BANCORP</issuerName>
        <issuerTradingSymbol>PACW</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001091449</rptOwnerCik>
            <rptOwnerName>ROSE JOHN W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>401 WEST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92101</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18595</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>600</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Immediate Family Member</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3846153</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As principal of CapGen Capital Group II LLC</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">As of January 14, 2009, CapGen Capital Group II LP (&quot;CapGen LP&quot;) directly owned 3,846,153 shares of common stock, par value $0.01, of PacWest Bancorp. As a principal and a member of the investment committee of CapGen Capital Group II LLC, the general partner of CapGen LP, Mr. Rose may be deemed to be the indirect beneficial owner of such shares under Rule 16a-1(a)(2) promulgated under the Securities Exchange Act of 1934, as amended (the &quot;Exchange Act&quot;).  However, pursuant to Rule 16a-1(a)(4) promulgated under the Exchange Act, Mr. Rose disclaims that he is the beneficial owner of such shares, except to the extent of his pecuniary interest.</footnote>
        <footnote id="F2">A separate Form 3 is being filed by CapGen LP, together with CapGen Capital Group II LLC and Mr. Eugene Ludwig, with respect to these shares.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>John W. Rose</signatureName>
        <signatureDate>2009-01-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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