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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 MgYN4/3+hUbx1qrJxMc+p6sl5hu/vdassBEjQAivG0VpenovAVIR1330c1IJX/+j
 Xu3ecju7dvYrG0XV/QJrCQ==

<SEC-DOCUMENT>0000921895-09-001369.txt : 20090512
<SEC-HEADER>0000921895-09-001369.hdr.sgml : 20090512
<ACCEPTANCE-DATETIME>20090512172432
ACCESSION NUMBER:		0000921895-09-001369
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090508
FILED AS OF DATE:		20090512
DATE AS OF CHANGE:		20090512

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KAUFMAN ALAN W
		CENTRAL INDEX KEY:			0001240887

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-23970
		FILM NUMBER:		09819830

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FALCONSTOR SOFTWARE INC
		CENTRAL INDEX KEY:			0000922521
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				770216135
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		125 BAYLIS ROAD
		CITY:			MELVILLE
		STATE:			NY
		ZIP:			11747
		BUSINESS PHONE:		631 777 5188

	MAIL ADDRESS:	
		STREET 1:		125 BAYLIS ROAD
		CITY:			MELVILLE
		STATE:			NY
		ZIP:			11747

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NETWORK PERIPHERALS INC
		DATE OF NAME CHANGE:	19940502
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>kau145.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-05-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000922521</issuerCik>
        <issuerName>FALCONSTOR SOFTWARE INC</issuerName>
        <issuerTradingSymbol>FALC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001240887</rptOwnerCik>
            <rptOwnerName>KAUFMAN ALAN W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O FALCONSTOR SOFTWARE, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2 HUNTINGTON QUADANGLE SUITE 2S01</rptOwnerStreet2>
            <rptOwnerCity>MELVILLE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>11747</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-05-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>25000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of Restricted Stock granted under the Company's 2007 Outside Directors Equity Compensation Plan, as amended.  The restrictions will lapse as to 33% of the shares on the date of each of the Company's next two annual meetings of stockholders.  The restrictions will lapse as to the remaining 34% of the shares on the date of the Company's 2012 annual meeting of stockholders.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Kaufman, Alan W.</signatureName>
        <signatureDate>2009-05-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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