<SUBMISSION>
<ACCESSION-NUMBER>0001181431-06-069153
<TYPE>3
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20061212
<FILING-DATE>20061212
<DATE-OF-FILING-DATE-CHANGE>20061212
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>IPG PHOTONICS CORP
<CIK>0001111928
<ASSIGNED-SIC>3674
<IRS-NUMBER>043444218
<STATE-OF-INCORPORATION>DE
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>50 OLD WEBSTER ROAD
<CITY>OXFORD
<STATE>MA
<ZIP>01540
<PHONE>5083731100
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>50 OLD WEBSTER ROAD
<CITY>OXFORD
<STATE>MA
<ZIP>01540
</MAIL-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>TA ADVENT VIII LP
<CIK>0001106837
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>3
<ACT>34
<FILE-NUMBER>001-33155
<FILM-NUMBER>061272427
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>125 HIGH ST
<CITY>BOSTON
<STATE>MA
<ZIP>02110
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>125 HIGH ST
<CITY>BOSTON
<STATE>MA
<ZIP>02110
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>rrd139124.xml
<DESCRIPTION>FORM 3
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2006-12-12</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001111928</issuerCik>
        <issuerName>IPG PHOTONICS CORP</issuerName>
        <issuerTradingSymbol>IPGP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001106837</rptOwnerCik>
            <rptOwnerName>TA ADVENT VIII LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>JOHN HANCOCK TOWER</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST, 56TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Series B Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2006-12-12</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>354767</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Series B Warrants</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2006-12-12</value>
            </exerciseDate>
            <expirationDate>
                <value>2008-04-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <footnoteId id="F2"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The number of shares of Common Stock is subject to adjustment based upon the initial public offering price in connection with the issuer's initial public offering.</footnote>
        <footnote id="F2">The number of shares of Common Stock underlying the warrants is indeterminate and will be determined based upon the initial public offering price of the Common Stock in connection with the issuer's initial public offering.</footnote>
        <footnote id="F3">N/A</footnote>
    </footnotes>

    <remarks>The Reporting Person has a representative on the issuer's board of directors.  Michael Child currently serves as the Reporting Person's representative on the board of directors and the Reporting Person is deemed a director of the issuer by deputization.</remarks>

    <ownerSignature>
        <signatureName>TA/Advent VIII L.P.</signatureName>
        <signatureDate>2006-12-12</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>By: TA Associates VIII LLC, its General Partner</signatureName>
        <signatureDate>2006-12-12</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>By: TA Associates, Inc., its Manager</signatureName>
        <signatureDate>2006-12-12</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>By: Thomas P. Alber, Chief Financial Officer</signatureName>
        <signatureDate>2006-12-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
