-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 RCveomc0T/zUHScY9z/JZU4k+a6vJpIl8gAmMmJtGnBbEIlRaMmwh/ip4rhuCfVG
 vtIMSgc0N/TKNf/IdQbUDg==

<SEC-DOCUMENT>0000880984-07-000008.txt : 20071113
<SEC-HEADER>0000880984-07-000008.hdr.sgml : 20071112
<ACCEPTANCE-DATETIME>20071113130753
ACCESSION NUMBER:		0000880984-07-000008
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070920
FILED AS OF DATE:		20071113
DATE AS OF CHANGE:		20071113

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ACORN FACTOR, INC.
		CENTRAL INDEX KEY:			0000880984
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER PROGRAMMING SERVICES [7371]
		IRS NUMBER:				222786081
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4 WEST ROCKLAND ROAD
		CITY:			MONTCHANIN
		STATE:			DE
		ZIP:			19710
		BUSINESS PHONE:		3026561708

	MAIL ADDRESS:	
		STREET 1:		4 WEST ROCKLAND ROAD
		CITY:			MONTCHANIN
		STATE:			DE
		ZIP:			19710

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	DATA SYSTEMS & SOFTWARE INC
		DATE OF NAME CHANGE:	19931019

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	DEFENSE SOFTWARE & SYSTEMS INC
		DATE OF NAME CHANGE:	19930328

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RIMER RICHARD S
		CENTRAL INDEX KEY:			0001338195

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19771
		FILM NUMBER:		071236495

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		41 22 737 00 40

	MAIL ADDRESS:	
		STREET 1:		17 CHEMIN DE LA SAPINIERE
		CITY:			VANDOEUVRES
		STATE:			V8
		ZIP:			1253
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-09-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000880984</issuerCik>
        <issuerName>ACORN FACTOR, INC.</issuerName>
        <issuerTradingSymbol>ACFN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001338195</rptOwnerCik>
            <rptOwnerName>RIMER RICHARD S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ACORN FACTOR, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>4 WEST ROCKLAND ROAD</rptOwnerStreet2>
            <rptOwnerCity>MONTCHANIN</rptOwnerCity>
            <rptOwnerState>DE</rptOwnerState>
            <rptOwnerZipCode>19710</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.35</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-09-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>25000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-11-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>25000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>25000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Part of a grant of options to purchase 100,000 shares referred to in footnote 1 to the Form 4 filed by the Reporting Person on December 1, 2006.  This Form 4 is filed to reflect the vesting of an additional 25,000 shares due to the satisfaction of certain performance criteria.  The Reporting Person has agreed to forfeit any right to exercise the remaining 50,000 options which were to vest upon the satisfaction of certain additional performance criteria.</footnote>
        <footnote id="F2">N/A</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Richard Rimer</signatureName>
        <signatureDate>2007-11-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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