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    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>
  <periodOfReport>2003-10-15</periodOfReport>
  <notSubjectToSection16>1</notSubjectToSection16>
    <issuer>
        <issuerCik>0000852772</issuerCik>
        <issuerName>DENNYS CORP</issuerName>
        <issuerTradingSymbol>DNYY</issuerTradingSymbol>
  </issuer>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000899983</rptOwnerCik>
            <rptOwnerName>GOTHAM PARTNERS LP /NY/</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>110 EAST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
      <isDirector>0</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>1</isTenPercentOwner>
      <isOther>0</isOther>
    </reportingOwnerRelationship>
  </reportingOwner>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001067815</rptOwnerCik>
            <rptOwnerName>GOTHAM PARNERS III L P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>110 EAST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
      <isDirector>0</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>1</isTenPercentOwner>
      <isOther>0</isOther>
    </reportingOwnerRelationship>
  </reportingOwner>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001078726</rptOwnerCik>
            <rptOwnerName>GOTHAM INTERNATIONAL ADVISORS LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>110 EAST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
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      <isDirector>0</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>1</isTenPercentOwner>
      <isOther>0</isOther>
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  </reportingOwner>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001056511</rptOwnerCik>
            <rptOwnerName>BERKOWITZ DAVID P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>110 EAST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
      <isDirector>0</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>1</isTenPercentOwner>
      <isOther>0</isOther>
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  </reportingOwner>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001056513</rptOwnerCik>
            <rptOwnerName>ACKMAN WILLIAM A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>110 EAST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
      <isDirector>0</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>1</isTenPercentOwner>
      <isOther>0</isOther>
    </reportingOwnerRelationship>
  </reportingOwner>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001056509</rptOwnerCik>
            <rptOwnerName>SECTION H PARTNERS L P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>110 EAST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
      <isDirector>0</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>1</isTenPercentOwner>
      <isOther>0</isOther>
    </reportingOwnerRelationship>
  </reportingOwner>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001251929</rptOwnerCik>
            <rptOwnerName>KARENINA CORP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>110 EAST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
      <isDirector>0</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>1</isTenPercentOwner>
      <isOther>0</isOther>
    </reportingOwnerRelationship>
  </reportingOwner>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001251930</rptOwnerCik>
            <rptOwnerName>DPB CORP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>110 EAST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
      <isDirector>0</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>1</isTenPercentOwner>
      <isOther>0</isOther>
    </reportingOwnerRelationship>
  </reportingOwner>
  <nonDerivativeTable>
    <nonDerivativeTransaction>
      <securityTitle>
        <value>Common Stock</value>
      </securityTitle>
      <transactionDate>
        <value>2003-10-15</value>
      </transactionDate>
      <transactionCoding>
        <transactionFormType>4</transactionFormType>
        <transactionCode>S</transactionCode>
        <equitySwapInvolved>0</equitySwapInvolved>
      </transactionCoding>
      <transactionTimeliness>
        <value></value>
      </transactionTimeliness>
      <transactionAmounts>
        <transactionShares>
          <value>3000000</value>
        </transactionShares>
        <transactionPricePerShare>
          <value>0.3125</value>
        </transactionPricePerShare>
        <transactionAcquiredDisposedCode>
          <value>D</value>
        </transactionAcquiredDisposedCode>
      </transactionAmounts>
      <postTransactionAmounts>
        <sharesOwnedFollowingTransaction>
          <value>2265952</value>
        </sharesOwnedFollowingTransaction>
      </postTransactionAmounts>
      <ownershipNature>
        <directOrIndirectOwnership>
          <value>I</value>
        </directOrIndirectOwnership>
        <natureOfOwnership>
          <value>See Footnotes</value>
          <footnoteId id="F1"/>
          <footnoteId id="F2"/>
        </natureOfOwnership>
      </ownershipNature>
    </nonDerivativeTransaction>
    <nonDerivativeTransaction>
      <securityTitle>
        <value>Common Stock</value>
      </securityTitle>
      <transactionDate>
        <value>2003-10-15</value>
      </transactionDate>
      <transactionCoding>
        <transactionFormType>4</transactionFormType>
        <transactionCode>S</transactionCode>
        <equitySwapInvolved>0</equitySwapInvolved>
      </transactionCoding>
      <transactionTimeliness>
        <value></value>
      </transactionTimeliness>
      <transactionAmounts>
        <transactionShares>
          <value>265952</value>
        </transactionShares>
        <transactionPricePerShare>
          <value>0.3000</value>
        </transactionPricePerShare>
        <transactionAcquiredDisposedCode>
          <value>D</value>
        </transactionAcquiredDisposedCode>
      </transactionAmounts>
      <postTransactionAmounts>
        <sharesOwnedFollowingTransaction>
          <value>2000000</value>
        </sharesOwnedFollowingTransaction>
      </postTransactionAmounts>
      <ownershipNature>
        <directOrIndirectOwnership>
          <value>I</value>
        </directOrIndirectOwnership>
        <natureOfOwnership>
          <value>See Footnotes</value>
          <footnoteId id="F1"/>
          <footnoteId id="F2"/>
        </natureOfOwnership>
      </ownershipNature>
    </nonDerivativeTransaction>
  </nonDerivativeTable>
  <footnotes>
    <footnote id="F1">Section H Partners, LP ("Section H") is the general partner of Gotham Partners, LP ("Gotham") and Gotham Partners III, LP ("GIII"). Section H disclaims any beneficial ownership of any of the Issuer's securities to which this Statement relates for the purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except as to securities representing Section H's pro rata partnership interest in, or interest in the profits of, Gotham and GIII. Karenina Corp. ("Karenina"), wholly owned by William A. Ackman, and DPB Corp. ("DPB"), wholly owned by David P. Berkowitz, are the general partners of Section H. Each of Karenina, DPB, Ackman and Berkowitz similarly disclaim any beneficial ownership of any of the Issuer's securities to which this Statement relates for the purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except as to securities in which each such person may be deemed to have an indirect pecuniary interest pursuant to Rule 16a-1(a)(2)(ii).</footnote>
    <footnote id="F2">Gotham International Advisors, L.L.C. ("Gotham Advisors") is the investment manager of Gotham Partners International, Ltd. ("Gotham International").  Gotham Advisors disclaims any beneficial ownership of any of the Issuer's securities to which this Statement relates for the purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except as to securities in which Gotham Advisors may be deemed to have an indirect pecuniary interest pursuant to Rule 16a-1 (a)(2)(ii).  William A. Ackman and David P. Berkowitz are the senior managing members of Gotham Advisors.  Each of Mr. Ackman and Mr. Berkowitz similarly disclaim any beneficial ownership of any of the Issuer's securities to which this Statement relates for the purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except as to securities in which each such person may be deemed to have an indirect pecuniary interest pursuant to Rule 16a-1(a )(2)(ii).</footnote>
  </footnotes>
  <ownerSignature>
    <signatureName>/s/ William A. Ackman, by power of attorney</signatureName>
    <signatureDate>2003-10-16</signatureDate>
  </ownerSignature>
</ownershipDocument>

