<SEC-DOCUMENT>0001022079-17-000120.txt : 20170424
<SEC-HEADER>0001022079-17-000120.hdr.sgml : 20170424
<ACCEPTANCE-DATETIME>20170424161833
ACCESSION NUMBER:		0001022079-17-000120
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170420
FILED AS OF DATE:		20170424
DATE AS OF CHANGE:		20170424

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:		3 GIRALDA FARMS
		CITY:			MADISON
		STATE:			NJ
		ZIP:			07940
		BUSINESS PHONE:		9735202700

	MAIL ADDRESS:	
		STREET 1:		3 GIRALDA FARMS
		CITY:			MADISON
		STATE:			NJ
		ZIP:			07940

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PREVOZNIK MICHAEL E
		CENTRAL INDEX KEY:			0001222679

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12215
		FILM NUMBER:		17778468

	MAIL ADDRESS:	
		STREET 1:		3 GIRALDA FARMS
		CITY:			MADISON
		STATE:			NJ
		ZIP:			07940
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_149306509747504.xml
<DESCRIPTION>FORM 4
<TEXT>
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        <issuerName>QUEST DIAGNOSTICS INC</issuerName>
        <issuerTradingSymbol>DGX</issuerTradingSymbol>
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            <rptOwnerName>PREVOZNIK MICHAEL E</rptOwnerName>
        </reportingOwnerId>
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            <rptOwnerStreet1>C/O QUEST DIAGNOSTICS INCORPORATED</rptOwnerStreet1>
            <rptOwnerStreet2>3 GIRALDA FARMS</rptOwnerStreet2>
            <rptOwnerCity>MADISON</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07940</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP &amp; General Counsel</officerTitle>
            <otherText></otherText>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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            <transactionDate>
                <value>2017-04-20</value>
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                <footnoteId id="F1"/>
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                    <value>1013</value>
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                <transactionPricePerShare>
                    <value>55.65</value>
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                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2020-02-10</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <value>Stock Options (Right to Buy)</value>
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            <exerciseDate>
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            <expirationDate>
                <value>2021-02-15</value>
            </expirationDate>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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    <footnotes>
        <footnote id="F1">This exercise and sale reported were effected pursuant to a Rule 10b5-1 sales plan adopted by the reporting person on February 10, 2017.</footnote>
        <footnote id="F2">The amount includes exempt purchases made under the Company's stock purchase plan since the date of the last filing on Form 4.</footnote>
        <footnote id="F3">These underlying shares were acquired on a periodic basis by the trustee of the Company's tax qualified Profit Sharing (401(k)) and/or Supplemental Deferred Compensation Plan. The information was obtained from the plan administrator as of a current date. The number of shares is based on the account balance of the Company stock fund under each Plan (which includes some money market instruments) divided by the market price of the Company's stock as of that date.</footnote>
        <footnote id="F4">The options vested in three equal annual installments beginning with the first on February 10, 2011, the second on February 10, 2012 and the final on February 10, 2013.</footnote>
        <footnote id="F5">The options vested in three equal annual installments beginning with the first on February 15, 2012, the second on February 15, 2013 and the final on February 15, 2014.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ William J. O'Shaughnessy, Jr., Attorney in Fact for Michael E. Prevoznik</signatureName>
        <signatureDate>2017-04-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</DOCUMENT>
</SEC-DOCUMENT>
