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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001210193-07-000007.txt : 20071214
<SEC-HEADER>0001210193-07-000007.hdr.sgml : 20071214
<ACCEPTANCE-DATETIME>20071214140306
ACCESSION NUMBER:		0001210193-07-000007
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20071212
FILED AS OF DATE:		20071214
DATE AS OF CHANGE:		20071214

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROCHE ROBERT P JR
		CENTRAL INDEX KEY:			0001210193

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19119
		FILM NUMBER:		071306915

	MAIL ADDRESS:	
		STREET 1:		145 BRANDYWINE PARKWAY
		CITY:			WEST CHESTER
		STATE:			PA
		ZIP:			19380

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CEPHALON INC
		CENTRAL INDEX KEY:			0000873364
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				232484489
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		41 MOORES ROAD
		CITY:			FRAZER
		STATE:			PA
		ZIP:			19355
		BUSINESS PHONE:		6103440200

	MAIL ADDRESS:	
		STREET 1:		41 MOORES ROAD
		CITY:			FRAZER
		STATE:			PA
		ZIP:			19355
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
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        <issuerName>CEPHALON INC</issuerName>
        <issuerTradingSymbol>CEPH</issuerTradingSymbol>
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            <rptOwnerStreet2></rptOwnerStreet2>
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            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19355</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
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            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Exec VP, WW Pharmaceutical Ops</officerTitle>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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                <sharesOwnedFollowingTransaction>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2007-12-12</value>
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            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>1292</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>75.82</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
                    <value>57238</value>
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        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2007-12-12</value>
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                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
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                <transactionPricePerShare>
                    <value>75.81</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
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            <ownershipNature>
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            <securityTitle>
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            <transactionDate>
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                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
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                </transactionShares>
                <transactionPricePerShare>
                    <value>75.80</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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                <sharesOwnedFollowingTransaction>
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                <transactionShares>
                    <value>1069</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>75.78</value>
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                <transactionAcquiredDisposedCode>
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                </transactionAcquiredDisposedCode>
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                <value>Common Stock</value>
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                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>1077</value>
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                <transactionPricePerShare>
                    <value>75.76</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                    <value>2000</value>
                </transactionShares>
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                    <value>75.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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                </transactionAcquiredDisposedCode>
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    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Carolyn S. Iosca, Attorney-in-Fact For: Robert P. Roche, Jr.</signatureName>
        <signatureDate>2007-12-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----