<SEC-DOCUMENT>0000921895-11-002107.txt : 20111107
<SEC-HEADER>0000921895-11-002107.hdr.sgml : 20111107
<ACCEPTANCE-DATETIME>20111107193831
ACCESSION NUMBER:		0000921895-11-002107
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20111104
FILED AS OF DATE:		20111107
DATE AS OF CHANGE:		20111107

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Strumingher Jennifer
		CENTRAL INDEX KEY:			0001532975

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22563
		FILM NUMBER:		111185941

	MAIL ADDRESS:	
		STREET 1:		C/O SG BLOCKS, INC.
		STREET 2:		400 MADISON AVENUE, SUITE 16C
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CDSI HOLDINGS INC
		CENTRAL INDEX KEY:			0001023994
		STANDARD INDUSTRIAL CLASSIFICATION:	BLANK CHECKS [6770]
		IRS NUMBER:				954463937
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		100 S E SECOND STREET
		CITY:			MIAMI
		STATE:			FL
		ZIP:			33131
		BUSINESS PHONE:		3055798000

	MAIL ADDRESS:	
		STREET 1:		100 S E SECOND STREET
		CITY:			MIAMI
		STATE:			FL
		ZIP:			33131

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PC411 INC
		DATE OF NAME CHANGE:	19961001
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>form308066003f_11072011.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0204</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2011-11-04</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001023994</issuerCik>
        <issuerName>CDSI HOLDINGS INC</issuerName>
        <issuerTradingSymbol>CDSI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001532975</rptOwnerCik>
            <rptOwnerName>Strumingher Jennifer</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SG BLOCKS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>400 MADISON AVENUE, SUITE 16C</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Administrative Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>Jennifer Strumingher</signatureName>
        <signatureDate>2011-11-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
