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

    <schemaVersion>X0204</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2011-08-11</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001160165</issuerCik>
        <issuerName>ShengdaTech, Inc.</issuerName>
        <issuerTradingSymbol>SDTHQ</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001533551</rptOwnerCik>
            <rptOwnerName>Wellesley Investment Advisors</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>20 WILLIAM STREET, SUITE G-5</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WELLESLEY</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02481</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>See Remarks</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>6.5% Senior Convertible Notes Due 2015</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.07</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-12-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1511034</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Notes are convertible by the holder at any time.</footnote>
        <footnote id="F2">The reporting person serves as investment manager for investment accounts that hold these securities. The reporting person disclaims beneficial ownership of these securities except to the extent of its pecuniary interest therein, if any.</footnote>
    </footnotes>

    <remarks>Remarks:

The reporting person has a relationship with other security holders of the issuer who, in the aggregate, may be deemed to beneficially own, as a result of their ownership of convertible debt securities of the issuer, more than 10% of the issuer's common stock as determined under Section 13(d) of the Securities Exchange Act of 1934. The reporting person disclaims membership in a &quot;group&quot; with those security holders as that term is used in Section 13(d) and denies that it, or any entity for which it serves as investment manager, is subject to Section 16 of the Securities Exchange Act of 1934 with respect to its ownership of or transactions in equity securities of the issuer. The reporting person is filing this Form 3 for informational purposes, and the filing of this Form 3 shall not be deemed an admission that the reporting person is a member of such a group or is otherwise subject to Section 16.</remarks>

    <ownerSignature>
        <signatureName>/s/ Greg Miller, Chief Executive Officer</signatureName>
        <signatureDate>2011-10-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
