<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2009-12-02</periodOfReport>

    <dateOfOriginalSubmission>2008-09-12</dateOfOriginalSubmission>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001448397</issuerCik>
        <issuerName>Seanergy Maritime Holdings Corp.</issuerName>
        <issuerTradingSymbol>SHIP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001439357</rptOwnerCik>
            <rptOwnerName>Nisswa Acquisition Master Fund Ltd.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MAPLES CORPORATE SVCS LIMITED</rptOwnerStreet1>
            <rptOwnerStreet2>PO BOX 309, UGLAND HOUSE</rptOwnerStreet2>
            <rptOwnerCity>GRAND CAYMAN</rptOwnerCity>
            <rptOwnerState>E9</rptOwnerState>
            <rptOwnerZipCode>KY1-1104</rptOwnerZipCode>
            <rptOwnerStateDescription>CAYMAN ISLANDS</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>no longer 10% owners</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Warrants</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.5</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2008-09-24</value>
            </exerciseDate>
            <expirationDate>
                <value>2011-09-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3260012</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <remarks>According to the Form 6-K filed by the Issuer on December 3, 2009, it had issued 4,308,075 shares of its common stock pursuant to the earn-out
provision contained in the acquisition agreement associated with the Issuer's 2008 business combination. As of that date, the Reporting Person no
longer had reporting obligations under Section 16. The Reporting Person met all of its filing oblgiations under Section 16 and the &quot;Date of Earliest
Transaction&quot; referenced hereinabove is the date of the Form 6-K referred to in this response. This Form 4 is being filed, not due to a statutory
requirement, but rather as notice that the Reporting Person is no longer subject to Section 16 with respect to the Issuer, since it is not currently a
10% owner.</remarks>

    <ownerSignature>
        <signatureName>Nisswa Acquisition Master Fund Ltd., By: Pine River Capital Management L.P., its Investment Manager, By: Pine River Capital Management LLC, its General Partner, By: Brian Taylor</signatureName>
        <signatureDate>2009-12-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
