<SUBMISSION>
<ACCESSION-NUMBER>0001237899-04-000011
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20040109
<FILING-DATE>20040112
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>REGENERON PHARMACEUTICALS INC
<CIK>0000872589
<ASSIGNED-SIC>2834
<IRS-NUMBER>133444607
<STATE-OF-INCORPORATION>NY
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>777 OLD SAW MILL RIVER RD
<CITY>TARRYTOWN
<STATE>NY
<ZIP>10591-6707
<PHONE>9143477000
</BUSINESS-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>GOLDBERG MURRAY A
<CIK>0001226435
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-19034
<FILM-NUMBER>04519749
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>REGENERON PHARMACEUTICALS INC
<STREET2>777 OLD SAW MILL RIVER RD
<CITY>TARRYTOWN
<STATE>NY
<ZIP>10591
<PHONE>9143457491
</BUSINESS-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
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            <rptOwnerStreet2></rptOwnerStreet2>
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            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isTenPercentOwner>0</isTenPercentOwner>
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                <transactionShares>
                    <value>28</value>
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                <transactionPricePerShare>
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                </directOrIndirectOwnership>
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        </nonDerivativeTransaction>

        <nonDerivativeTransaction>
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                </directOrIndirectOwnership>
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        </nonDerivativeTransaction>

        <nonDerivativeTransaction>
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                <value>Common Stock</value>
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            <transactionAmounts>
                <transactionShares>
                    <value>28</value>
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                <transactionPricePerShare>
                    <value>15.18</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                <directOrIndirectOwnership>
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        </nonDerivativeTransaction>

    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Disposition made pursuant to a plan intended to comply with Rule 10b5-1(c).</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>**/s/Murray A. Goldberg</signatureName>
        <signatureDate>2004-01-12</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
