-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
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 TQYHV39X2imqsw/O5IoF/A==

<SEC-DOCUMENT>0000919574-10-006111.txt : 20101103
<SEC-HEADER>0000919574-10-006111.hdr.sgml : 20101103
<ACCEPTANCE-DATETIME>20101103175826
ACCESSION NUMBER:		0000919574-10-006111
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101101
FILED AS OF DATE:		20101103
DATE AS OF CHANGE:		20101103

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			AUERBACH JONATHAN A G
		CENTRAL INDEX KEY:			0001176208

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15288
		FILM NUMBER:		101162582

	MAIL ADDRESS:	
		STREET 1:		215 E 73RD STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10021

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NETWORK 1 SECURITY SOLUTIONS INC
		CENTRAL INDEX KEY:			0001065078
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				113027591
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1601 TRAPELO RD
		STREET 2:		RESERVOIR PLACE
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		7815223400

	MAIL ADDRESS:	
		STREET 1:		1601 TRAPELO RD
		STREET 2:		RESERVOIR PLACE
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hound Partners, LLC
		CENTRAL INDEX KEY:			0001353316
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15288
		FILM NUMBER:		101162584

	BUSINESS ADDRESS:	
		STREET 1:		101 PARK AVENUE
		STREET 2:		48TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10178
		BUSINESS PHONE:		212-984-2500

	MAIL ADDRESS:	
		STREET 1:		101 PARK AVENUE
		STREET 2:		48TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10178

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hound Performance, LLC
		CENTRAL INDEX KEY:			0001375882
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15288
		FILM NUMBER:		101162583

	BUSINESS ADDRESS:	
		STREET 1:		101 PARK AVENUE
		STREET 2:		48TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10178
		BUSINESS PHONE:		(212) 984-2500

	MAIL ADDRESS:	
		STREET 1:		101 PARK AVENUE
		STREET 2:		48TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10178
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>p1144425.xml
<DESCRIPTION>HOUND PARTNERS/NSSI
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-11-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001065078</issuerCik>
        <issuerName>NETWORK 1 SECURITY SOLUTIONS INC</issuerName>
        <issuerTradingSymbol>NSSI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001353316</rptOwnerCik>
            <rptOwnerName>Hound Partners, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>101 PARK AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>48TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10178</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001375882</rptOwnerCik>
            <rptOwnerName>Hound Performance, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>101 PARK AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>48TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10178</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001176208</rptOwnerCik>
            <rptOwnerName>AUERBACH JONATHAN A G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>101 PARK AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>48TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10178</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock $.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-01</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2010-11-01</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1495</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>722959</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Hound Partners, LP</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock $.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-01</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2010-11-01</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1742</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1055960</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Hound Partners Offshore Fund, LP</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock $.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-01</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2010-11-01</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>463</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>194964</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Hound Partners, LLC</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock $.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-02</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2010-11-02</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1051</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>721908</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Hound Partners, LP</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock $.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-02</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2010-11-02</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1224</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1054736</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Hound Partners Offshore Fund, LP</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock $.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-02</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2010-11-02</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>325</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>194639</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Hound Partners, LLC</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The securities may be deemed to be beneficially owned by (a) Hound Performance, LLC, the general partner of Hound Partners, LP; (b) Hound Partners, LLC, the investment manager of Hound Partners, LP and (c) Jonathan Auerbach, the managing member of Hound Performance, LLC and Hound Partners, LLC.  Each Reporting Person disclaims beneficial ownership in the securities reported on this Form 4 except to the extent of his or its pecuniary interest, if any, therein, and this report shall not be deemed to be an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F2">The securities may be deemed to be beneficially owned by (a) Hound Performance, LLC, the general partner of Hound Partners Offshore Fund, LP; (b) Hound Partners, LLC, the investment manager of Hound Partners Offshore Fund, LP and (c) Jonathan Auerbach, the managing member of Hound Performance, LLC and Hound Partners, LLC.  Each Reporting Person disclaims beneficial ownership in the securities reported on this Form 4 except to the extent of his or its pecuniary interest, if any, therein, and this report shall not be deemed to be an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F3">The securities may be deemed to be beneficially owned by (a) Hound Partners, LLC; (b) a separately managed account managed by Hound Partners, LLC and (c) Jonathan Auerbach, the managing member of Hound Partners, LLC.  Each Reporting Person disclaims beneficial ownership in the securities reported on this Form 4 except to the extent of his or its pecuniary interest, if any, therein, and this report shall not be deemed to be an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Hound Partners, LLC, By: /s/ Jonathan Auerbach, Managing Member</signatureName>
        <signatureDate>2010-11-03</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Hound Performance, LLC, By: /s/ Jonathan Auerbach, Managing Member</signatureName>
        <signatureDate>2010-11-03</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Jonathan Auerbach</signatureName>
        <signatureDate>2010-11-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
