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    <issuer>
        <issuerCik>0000038984</issuerCik>
        <issuerName>SIGNATURE GROUP HOLDINGS INC</issuerName>
        <issuerTradingSymbol>SGGH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000922294</rptOwnerCik>
            <rptOwnerName>GROSSMAN KENNETH S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CLINTON GROUP</rptOwnerStreet1>
            <rptOwnerStreet2>9 WEST 57TH ST. 26 TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
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            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
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    <footnotes></footnotes>

    <remarks>On August 2, 2011, pursuant to his Employment Agreement and subject to the terms of his Restricted Stock Award Agreement (&quot;the RSA&quot;) Mr. Grossman was granted 492,224 restricted shares of Signature Group Holdings, Inc. (&quot;the Company&quot;) common stock which shall vest on December 31, 2013.

On August 8, 2011, pursuant to his Employment Agreement and subject to the terms of his Non-Qualified Stock Option Agreement (&quot;the Option Agreement&quot;), Mr. Grossman was granted options to purchase 2,930,000 shares of Signature Group Holdings, Inc. (&quot;the Company&quot;) common stock at the average of the closing prices of the Company's common stock for the 3 business-day period ending on the business day immediately before the award date, subject to adjustment pursuant to the terms of the Company's 2006 Performance Incentive Plan.  The options shall vest as follows: (i) 25% on the 6 month anniversary of the award date; (ii) 25% on the 18 month anniversary of the award date; (iii) 25% on the 30 month anniversary of the award date; and (iv) 25% on July 1, 2015, with this final tranche subject to the Company's common stock achieving certain trading prices as of such date.

See the Company's Form 8-K/A filed on August 4, 2011 for further details.</remarks>

    <ownerSignature>
        <signatureName>/s/ Kenneth Grossman</signatureName>
        <signatureDate>2011-08-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
