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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3/A</documentType>

    <periodOfReport>2015-06-08</periodOfReport>

    <dateOfOriginalSubmission>2015-06-08</dateOfOriginalSubmission>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000921547</issuerCik>
        <issuerName>HERITAGE OAKS BANCORP</issuerName>
        <issuerTradingSymbol>HEOP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001459707</rptOwnerCik>
            <rptOwnerName>CASTLE CREEK CAPITAL PARTNERS IV, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CASTLE CREEK CAPITAL LLC</rptOwnerStreet1>
            <rptOwnerStreet2>6051 EL TORDO</rptOwnerStreet2>
            <rptOwnerCity>RANCHO SANTA FE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92067</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001569797</rptOwnerCik>
            <rptOwnerName>Castle Creek Capital IV LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CASTLE CREEK CAPITAL LLC</rptOwnerStreet1>
            <rptOwnerStreet2>6051 EL TORDO</rptOwnerStreet2>
            <rptOwnerCity>RANCHO SANTA FE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92067</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001197257</rptOwnerCik>
            <rptOwnerName>EGGEMEYER JOHN M III</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CASTLE CREEK CAPITAL LLC</rptOwnerStreet1>
            <rptOwnerStreet2>6051 EL TORDO</rptOwnerStreet2>
            <rptOwnerCity>RANCHO SANTA FE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92067</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001242722</rptOwnerCik>
            <rptOwnerName>THOMAS J MIKESELL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CASTLE CREEK CAPITAL LLC</rptOwnerStreet1>
            <rptOwnerStreet2>6051 EL TORDO</rptOwnerStreet2>
            <rptOwnerCity>RANCHO SANTA FE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92067</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001332829</rptOwnerCik>
            <rptOwnerName>MERLO MARK G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CASTLE CREEK CAPITAL LLC</rptOwnerStreet1>
            <rptOwnerStreet2>6051 EL TORDO</rptOwnerStreet2>
            <rptOwnerCity>RANCHO SANTA FE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92067</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001481798</rptOwnerCik>
            <rptOwnerName>Pietrzak John</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CASTLE CREEK CAPITAL LLC</rptOwnerStreet1>
            <rptOwnerStreet2>6051 EL TORDO</rptOwnerStreet2>
            <rptOwnerCity>RANCHO SANTA FE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92067</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Heritage Oaks Bancorp Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3672638</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These securities are owned by Castle Creek Capital Partners IV, LP (&quot;Fund IV&quot;).  Each of Castle Creek Capital IV LLC, John M. Eggemeyer III, J. Mikesell Thomas, Mark G. Merlo, and John T. Pietrzak may also be deemed to be the beneficial owner of the 3,672,638 shares of Common Stock held directly by Fund IV.  Mr. Eggemeyer, Mr. Thomas, Mr. Merlo, and Mr. Pietrzak are managing principals of Castle Creek Capital IV LLC, the sole general partner of Fund IV.  Castle Creek Capital IV LLC, Mr. Eggemeyer, Mr. Thomas, Mr. Merlo, and Mr. Pietrzak each disclaim beneficial ownership of such shares of Common Stock, except to the extent of their respective pecuniary interest in Fund IV, and this report shall not be deemed an admission that Castle Creek Capital IV LLC, Mr. Eggemeyer, Mr. Thomas, Mr. Merlo, or Mr. Pietrzak is the beneficial owner of such shares of Common Stock for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.</footnote>
    </footnotes>

    <remarks>This Amended Form 3 is being filed solely to include J. Mikesell Thomas, Mark G. Merlo, and John T. Pietrzak as reporting persons for Heritage Oaks Bancorp.  Mr. Thomas, Mr. Merlo, and Mr. Pietrzak became managing principals of Castle Creek Capital Partners IV LLC on April 13, 2015.</remarks>

    <ownerSignature>
        <signatureName>CASTLE CREEK CAPITAL PARTNERS IV, LP, By: /s/ John M. Eggemeyer III, Name: John M. Eggemeyer III, Title: President</signatureName>
        <signatureDate>2015-11-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>CASTLE CREEK CAPITAL IV LLC, By: /s/ John M. Eggemeyer III, Name: John M. Eggemeyer III, Title: President</signatureName>
        <signatureDate>2015-11-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>JOHN M. EGGEMEYER III, By: /s/ John M. Eggemeyer III, Name: John M. Eggemeyer III</signatureName>
        <signatureDate>2015-11-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>J. MIKESELL THOMAS, By: /s/ J. Mikesell Thomas, Name: J. Mikesell Thomas</signatureName>
        <signatureDate>2015-11-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>MARK G. MERLO, By: /s/ Mark G. Merlo, Name: Mark G. Merlo</signatureName>
        <signatureDate>2015-11-09</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>JOHN T. PIETRZAK, By: /s/ John T. Pietrzak, Name: John T. Pietrzak</signatureName>
        <signatureDate>2015-11-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
