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          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>UnitedHealth Group Inc</name>
        <lei>549300GHBMY8T5GXDE41</lei>
        <title>UnitedHealth Group Inc</title>
        <cusip>91324P102</cusip>
        <identifiers>
          <isin value="US91324P1021"/>
        </identifiers>
        <balance>172.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>56778.92000000</valUSD>
        <pctVal>2.422431204429</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Vaxcyte Inc</name>
        <lei>254900M7NMHTGASX8D95</lei>
        <title>Vaxcyte Inc</title>
        <cusip>92243G108</cusip>
        <identifiers>
          <isin value="US92243G1085"/>
        </identifiers>
        <balance>952.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>43925.28000000</valUSD>
        <pctVal>1.874040029913</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Veeva Systems Inc</name>
        <lei>549300YZEXPDB92M2F02</lei>
        <title>Veeva Systems Inc</title>
        <cusip>922475108</cusip>
        <identifiers>
          <isin value="US9224751084"/>
        </identifiers>
        <balance>190.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>42413.70000000</valUSD>
        <pctVal>1.809549571835</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Morgan Stanley &amp; Co. LLC</name>
        <lei>549300OJY9IZ31SGS926</lei>
        <title>Morgan Stanley Institutional Liquidity Funds - Treasury Securities Portfolio</title>
        <cusip>61747C525</cusip>
        <identifiers>
          <isin value="US61747C5250"/>
        </identifiers>
        <balance>30388.16063198</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>30388.16063198</valUSD>
        <pctVal>1.296488706726</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>STIV</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <cashCollateralCondition cashCollateralVal="30388.16063198" isCashCollateral="Y"/>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Vertex Pharmaceuticals Inc</name>
        <lei>54930015RAQRRZ5ZGJ91</lei>
        <title>Vertex Pharmaceuticals Inc</title>
        <cusip>92532F100</cusip>
        <identifiers>
          <isin value="US92532F1003"/>
        </identifiers>
        <balance>128.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>58030.08000000</valUSD>
        <pctVal>2.475811033170</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>West Pharmaceutical Services Inc</name>
        <lei>5493007NKRGM1RJQ1P16</lei>
        <title>West Pharmaceutical Services Inc</title>
        <cusip>955306105</cusip>
        <identifiers>
          <isin value="US9553061055"/>
        </identifiers>
        <balance>146.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>40170.44000000</valUSD>
        <pctVal>1.713842520281</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Morgan Stanley &amp; Co. LLC</name>
        <lei>549300OJY9IZ31SGS926</lei>
        <title>Morgan Stanley Institutional Liquidity Funds - Treasury Securities Portfolio</title>
        <cusip>61747C525</cusip>
        <identifiers>
          <isin value="US61747C5250"/>
        </identifiers>
        <balance>91460.56000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>91460.56000000</valUSD>
        <pctVal>3.902098076514</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>STIV</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Zoetis Inc</name>
        <lei>549300HD9Q1LOC9KLJ48</lei>
        <title>Zoetis Inc</title>
        <cusip>98978V103</cusip>
        <identifiers>
          <isin value="US98978V1035"/>
        </identifiers>
        <balance>411.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>51712.02000000</valUSD>
        <pctVal>2.206255611978</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>HSBC Securities (USA) Inc.</name>
        <lei>CYYGQCGNHMHPSMRL3R97</lei>
        <title>HSBC TRI PARTY   A REPO</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="99VDKG003_X_SLCOLLCASH"/>
        </identifiers>
        <balance>3100.83271375</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>3100.83271375</valUSD>
        <pctVal>0.132294765830</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>RA</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <repurchaseAgrmt>
          <transCat>Repurchase</transCat>
          <notClearedCentCparty isCleared="N">
            <counterpartyInfos>
              <counterpartyInfo lei="CYYGQCGNHMHPSMRL3R97" name="HSBC Securities (USA) Inc."/>
            </counterpartyInfos>
          </notClearedCentCparty>
          <isTriParty>Y</isTriParty>
          <repurchaseRt>3.83000000</repurchaseRt>
          <maturityDt>2026-01-02</maturityDt>
          <repurchaseCollaterals>
            <repurchaseCollateral>
              <principalAmt>3234.01780100</principalAmt>
              <principalCd>USD</principalCd>
              <collateralVal>3162.85000679</collateralVal>
              <collateralCd>USD</collateralCd>
              <invstCat>UST</invstCat>
            </repurchaseCollateral>
          </repurchaseCollaterals>
        </repurchaseAgrmt>
        <securityLending>
          <cashCollateralCondition cashCollateralVal="3100.83271375" isCashCollateral="Y"/>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Merrill Lynch, Pierce, Fenner &amp; Smith Incorporated</name>
        <lei>8NAV47T0Y26Q87Y0QP81</lei>
        <title>MERRILL LYNCH TRI PARTY A REPO</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="99VDMN006_1_X_SLCOLLCASH"/>
        </identifiers>
        <balance>7441.99851300</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>7441.99851300</valUSD>
        <pctVal>0.317507437992</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>RA</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <repurchaseAgrmt>
          <transCat>Repurchase</transCat>
          <notClearedCentCparty isCleared="N">
            <counterpartyInfos>
              <counterpartyInfo lei="8NAV47T0Y26Q87Y0QP81" name="Merrill Lynch, Pierce, Fenner &amp; Smith Incorporated"/>
            </counterpartyInfos>
          </notClearedCentCparty>
          <isTriParty>Y</isTriParty>
          <repurchaseRt>3.82000000</repurchaseRt>
          <maturityDt>2026-01-02</maturityDt>
          <repurchaseCollaterals>
            <repurchaseCollateral>
              <principalAmt>12977.61518000</principalAmt>
              <principalCd>USD</principalCd>
              <collateralVal>7590.86333311</collateralVal>
              <collateralCd>USD</collateralCd>
              <invstCat>UST</invstCat>
            </repurchaseCollateral>
          </repurchaseCollaterals>
        </repurchaseAgrmt>
        <securityLending>
          <cashCollateralCondition cashCollateralVal="7441.99851300" isCashCollateral="Y"/>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Merrill Lynch, Pierce, Fenner &amp; Smith Incorporated</name>
        <lei>8NAV47T0Y26Q87Y0QP81</lei>
        <title>MERRILL LYNCH TRI PARTY A REPO</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="99VDMN006_2_X_SLCOLLCASH"/>
        </identifiers>
        <balance>961.25814126</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>961.25814126</valUSD>
        <pctVal>0.041011377407</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>RA</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <repurchaseAgrmt>
          <transCat>Repurchase</transCat>
          <notClearedCentCparty isCleared="N">
            <counterpartyInfos>
              <counterpartyInfo lei="8NAV47T0Y26Q87Y0QP81" name="Merrill Lynch, Pierce, Fenner &amp; Smith Incorporated"/>
            </counterpartyInfos>
          </notClearedCentCparty>
          <isTriParty>Y</isTriParty>
          <repurchaseRt>3.65000000</repurchaseRt>
          <maturityDt>2026-01-02</maturityDt>
          <repurchaseCollaterals>
            <repurchaseCollateral>
              <principalAmt>958.28134200</principalAmt>
              <principalCd>USD</principalCd>
              <collateralVal>980.46226183</collateralVal>
              <collateralCd>USD</collateralCd>
              <invstCat>UST</invstCat>
            </repurchaseCollateral>
          </repurchaseCollaterals>
        </repurchaseAgrmt>
        <securityLending>
          <cashCollateralCondition cashCollateralVal="961.25814126" isCashCollateral="Y"/>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Atai Beckley NV</name>
        <lei>391200Z8UWPJSNBNCA11</lei>
        <title>Atai Beckley NV</title>
        <cusip>000000000</cusip>
        <identifiers>
          <isin value="NL0015000DX5"/>
        </identifiers>
        <balance>9857.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>40315.13000000</valUSD>
        <pctVal>1.720015613587</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>NL</invCountry>

        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <loanByFundCondition isLoanByFund="Y" loanVal="40315.13000000"/>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Newamsterdam Pharma Co NV</name>
        <lei>984500B6549TF6E14D36</lei>
        <title>Newamsterdam Pharma Co NV</title>
        <cusip>000000000</cusip>
        <identifiers>
          <isin value="NL00150012L7"/>
        </identifiers>
        <balance>2383.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>83595.64000000</valUSD>
        <pctVal>3.566547001778</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>NL</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>uniQure NV</name>
        <lei>724500RPCTZLFYJZ3S98</lei>
        <title>uniQure NV</title>
        <cusip>000000000</cusip>
        <identifiers>
          <isin value="NL0010696654"/>
        </identifiers>
        <balance>746.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>17851.78000000</valUSD>
        <pctVal>0.761633171722</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>NL</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
    </invstOrSecs>
    <explntrNotes>
      <explntrNote note="Monthly returns presented in Item B.5(a) have been calculated without deducting any applicable sales loads or redemption fees." noteItem="B.5.a"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2026-01-16</ncom:dateSigned>
      <ncom:nameOfApplicant>MORGAN STANLEY INSTITUTIONAL FUND INC</ncom:nameOfApplicant>
      <ncom:signature>Francis Smith</ncom:signature>
      <ncom:signerName>Francis Smith</ncom:signerName>
      <ncom:title>Principal Financial Officer</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
