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    <isConfidential>false</isConfidential>
    <filerInfo>

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          <cik>0000899148</cik>
          <ccc>XXXXXXXX</ccc>
        </issuerCredentials>
      </filer>


      <seriesClassInfo>
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        <classId>C000010454</classId>
        <classId>C000010456</classId>
        <classId>C000010455</classId>
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      <regFileNumber>811-07584</regFileNumber>
      <regCik>0000899148</regCik>
      <regLei>5493004D62WV1EDNTU07</regLei>
      <regStreet1>702 King Farm Blvd., Suite 200</regStreet1>
      <regCity>Rockville</regCity>
      <regStateConditional regCountry="US" regState="US-MD"/>
      <regZipOrPostalCode>20850</regZipOrPostalCode>
      <regPhone>301-296-5100</regPhone>
      <seriesName>Inverse Mid-Cap Strategy Fund</seriesName>
      <seriesId>S000003771</seriesId>
      <seriesLei>54930037B8QM4B0GQX38</seriesLei>
      <repPdEnd>2021-03-31</repPdEnd>
      <repPdDate>2020-06-30</repPdDate>
      <isFinalFiling>N</isFinalFiling>
    </genInfo>
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      <totLiabs>47205.76</totLiabs>
      <netAssets>1639061.68</netAssets>
      <assetsAttrMiscSec>0.00000000</assetsAttrMiscSec>
      <assetsInvested>0.00000000</assetsInvested>
      <amtPayOneYrBanksBorr>0.00000000</amtPayOneYrBanksBorr>
      <amtPayOneYrCtrldComp>0.00000000</amtPayOneYrCtrldComp>
      <amtPayOneYrOthAffil>0.00000000</amtPayOneYrOthAffil>
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      <standByCommit>0.00000000</standByCommit>
      <liquidPref>0.00000000</liquidPref>
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      <isNonCashCollateral>N</isNonCashCollateral>
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      <invstOrSec>
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        <title>Guggenheim Ultra Short Duration Fund - Institutional Class</title>
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        <identifiers>
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        <fairValLevel>1</fairValLevel>
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      </invstOrSec>
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    <signature>
      <ncom:dateSigned>2020-07-30</ncom:dateSigned>
      <ncom:nameOfApplicant>Rydex Series Funds</ncom:nameOfApplicant>
      <ncom:signature>John Sullivan</ncom:signature>
      <ncom:signerName>John Sullivan</ncom:signerName>
      <ncom:title>CFO</ncom:title>
    </signature>
  </formData>
  <documents>XXXX</documents>
</edgarSubmission>
