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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 G1BSm1IzShE9EtUmxY/SLvMZ0VxCd9OWmNN0+lMXPs8P9x5fCZt4YMvuNdso8FXq
 na0OJql3BxbulhlGavPwJg==

<SEC-DOCUMENT>0001179110-05-010370.txt : 20050519
<SEC-HEADER>0001179110-05-010370.hdr.sgml : 20050519
<ACCEPTANCE-DATETIME>20050519151400
ACCESSION NUMBER:		0001179110-05-010370
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050519
FILED AS OF DATE:		20050519
DATE AS OF CHANGE:		20050519

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SPHERIX INC
		CENTRAL INDEX KEY:			0000012239
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ENGINEERING, ACCOUNTING, RESEARCH, MANAGEMENT [8700]
		IRS NUMBER:				520849320
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		12051 INDIAN CREEK CT
		CITY:			BELTSVILLE
		STATE:			MD
		ZIP:			20705
		BUSINESS PHONE:		3014193900

	MAIL ADDRESS:	
		STREET 1:		12051 INDIAN CREEK COURT
		CITY:			BELTSVILLE
		STATE:			MD
		ZIP:			20705

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BIOSPHERICS INC
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BIOSPHERICS RESEARCH INC
		DATE OF NAME CHANGE:	19720404

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ZANDEN ROBERT J VANDER
		CENTRAL INDEX KEY:			0001287601

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-05576
		FILM NUMBER:		05844649

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		973 316 9862

	MAIL ADDRESS:	
		STREET 1:		9 TIFFANY COURT
		CITY:			MONTVILLE
		STATE:			NJ
		ZIP:			07045 9165
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-05-19</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000012239</issuerCik>
        <issuerName>SPHERIX INC</issuerName>
        <issuerTradingSymbol>SPEX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001287601</rptOwnerCik>
            <rptOwnerName>ZANDEN ROBERT J VANDER</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>SPHERIX INCORPORATED</rptOwnerStreet1>
            <rptOwnerStreet2>12051 INDIAN CREEK COURT</rptOwnerStreet2>
            <rptOwnerCity>BELTSVILLE</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20705</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Common Stock Options</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.41</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-05-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-02-17</value>
            </exerciseDate>
            <expirationDate>
                <value>2005-02-16</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>N/A</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Robert J. Vander Zanden</signatureName>
        <signatureDate>2005-05-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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