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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001022079-07-000028.txt : 20070227
<SEC-HEADER>0001022079-07-000028.hdr.sgml : 20070227
<ACCEPTANCE-DATETIME>20070227181329
ACCESSION NUMBER:		0001022079-07-000028
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070226
FILED AS OF DATE:		20070227
DATE AS OF CHANGE:		20070227

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			QUEST DIAGNOSTICS INC
		CENTRAL INDEX KEY:			0001022079
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MEDICAL LABORATORIES [8071]
		IRS NUMBER:				161387862
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE MALCOLM AVE
		CITY:			TETERBORO
		STATE:			NJ
		ZIP:			07608
		BUSINESS PHONE:		2013935000

	MAIL ADDRESS:	
		STREET 1:		ONE MALCOLM AVE
		CITY:			TETERBORO
		STATE:			NJ
		ZIP:			07601

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CORNING CLINICAL LABORATORIES INC
		DATE OF NAME CHANGE:	19960903

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GRANT WILLIAM R
		CENTRAL INDEX KEY:			0001016359

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12215
		FILM NUMBER:		07654617

	BUSINESS ADDRESS:	
		STREET 1:		610 FIFTH AVENUE 5TH FLOOR
		STREET 2:		C/O GALEN ASSOCIATES
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10020
		BUSINESS PHONE:		2122184990

	MAIL ADDRESS:	
		STREET 1:		C/O GALEN ASSOCIATES
		STREET 2:		610 FIFTH AVENUE 5TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10020
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
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            <underlyingSecurity>
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                <underlyingSecurityShares>
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                <value></value>
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            <transactionAmounts>
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                <transactionPricePerShare>
                    <value>22.3812</value>
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            <transactionTimeliness>
                <value></value>
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            <transactionAmounts>
                <transactionShares>
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                <transactionPricePerShare>
                    <value>28.4175</value>
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    </derivativeTable>

    <footnotes>
        <footnote id="F1">The sales price of these shares represents an average sales price.</footnote>
        <footnote id="F2">Reporting Person will retire as a Director of Quest Diagnostics on May 8, 2007, when his current term expires.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Leo C. Farrenkopf, Jr., atty-in-fact for William R. Grant</signatureName>
        <signatureDate>2007-02-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----