<SUBMISSION>
<ACCESSION-NUMBER>0001140361-09-027860
<TYPE>4
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<PERIOD>20091201
<FILING-DATE>20091202
<DATE-OF-FILING-DATE-CHANGE>20091202
<REPORTING-OWNER>
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<CONFORMED-NAME>LACY PAUL A
<CIK>0001193635
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<ACT>34
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<FILM-NUMBER>091217324
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<MAIL-ADDRESS>
<STREET1>KRONOS INCORP
<STREET2>297 BILLERICA RD
<CITY>CHELMSFORD
<STATE>MA
<ZIP>01824
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<ISSUER>
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<CONFORMED-NAME>PARAMETRIC TECHNOLOGY CORP
<CIK>0000857005
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<IRS-NUMBER>042866152
<STATE-OF-INCORPORATION>MA
<FISCAL-YEAR-END>0930
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<BUSINESS-ADDRESS>
<STREET1>140 KENDRICK STREET
<CITY>NEEDHAM
<STATE>MA
<ZIP>02494
<PHONE>7813705000
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<MAIL-ADDRESS>
<STREET1>140 KENDRICK STREET
<CITY>NEEDHAM
<STATE>MA
<ZIP>02494
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<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <periodOfReport>2009-12-01</periodOfReport>

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            <rptOwnerZipCode>02494</rptOwnerZipCode>
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            <isDirector>1</isDirector>
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            <otherText></otherText>
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    <nonDerivativeTable>
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            <securityTitle>
                <value>Common Stock</value>
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                <transactionShares>
                    <value>16634</value>
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                <transactionPricePerShare>
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    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock award subject to a time-based restriction that vests in two equal installments of 8,317 shares on each of December 1, 2010 and December 1, 2011.</footnote>
        <footnote id="F2">Restricted stock award subject to a time-based restriction that vests on the earlier of Parametric Technology Corporation's 2010 Annual Meeting of Shareholders or March 15, 2010.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Catherine Gorecky by power of attorney filed 12/1/2009</signatureName>
        <signatureDate>2009-12-02</signatureDate>
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</ownershipDocument>
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</TEXT>
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</SUBMISSION>
