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      </Form990PartVIISectionAGrp>
      <Form990PartVIISectionAGrp>
        <PersonNm>JOHN P FISHER DDS</PersonNm>
        <TitleTxt>TRUSTEE</TitleTxt>
        <AverageHoursPerWeekRt>4.00</AverageHoursPerWeekRt>
        <AverageHoursPerWeekRltdOrgRt>1.00</AverageHoursPerWeekRltdOrgRt>
        <IndividualTrusteeOrDirectorInd>X</IndividualTrusteeOrDirectorInd>
        <ReportableCompFromOrgAmt>0</ReportableCompFromOrgAmt>
        <ReportableCompFromRltdOrgAmt>0</ReportableCompFromRltdOrgAmt>
        <OtherCompensationAmt>0</OtherCompensationAmt>
      </Form990PartVIISectionAGrp>
      <Form990PartVIISectionAGrp>
        <PersonNm>MARK J DOHERTY DMD</PersonNm>
        <TitleTxt>TRUSTEE</TitleTxt>
        <AverageHoursPerWeekRt>4.00</AverageHoursPerWeekRt>
        <AverageHoursPerWeekRltdOrgRt>1.00</AverageHoursPerWeekRltdOrgRt>
        <IndividualTrusteeOrDirectorInd>X</IndividualTrusteeOrDirectorInd>
        <ReportableCompFromOrgAmt>0</ReportableCompFromOrgAmt>
        <ReportableCompFromRltdOrgAmt>0</ReportableCompFromRltdOrgAmt>
        <OtherCompensationAmt>0</OtherCompensationAmt>
      </Form990PartVIISectionAGrp>
      <Form990PartVIISectionAGrp>
        <PersonNm>ROBERT S LELAND DMD</PersonNm>
        <TitleTxt>TRUSTEE</TitleTxt>
        <AverageHoursPerWeekRt>4.00</AverageHoursPerWeekRt>
        <AverageHoursPerWeekRltdOrgRt>1.00</AverageHoursPerWeekRltdOrgRt>
        <IndividualTrusteeOrDirectorInd>X</IndividualTrusteeOrDirectorInd>
        <ReportableCompFromOrgAmt>0</ReportableCompFromOrgAmt>
        <ReportableCompFromRltdOrgAmt>0</ReportableCompFromRltdOrgAmt>
        <OtherCompensationAmt>0</OtherCompensationAmt>
      </Form990PartVIISectionAGrp>
      <Form990PartVIISectionAGrp>
        <PersonNm>JAMES E MASLOWSKI DMD</PersonNm>
        <TitleTxt>TRUSTEE</TitleTxt>
        <AverageHoursPerWeekRt>4.00</AverageHoursPerWeekRt>
        <AverageHoursPerWeekRltdOrgRt>1.00</AverageHoursPerWeekRltdOrgRt>
        <IndividualTrusteeOrDirectorInd>X</IndividualTrusteeOrDirectorInd>
        <ReportableCompFromOrgAmt>0</ReportableCompFromOrgAmt>
        <ReportableCompFromRltdOrgAmt>0</ReportableCompFromRltdOrgAmt>
        <OtherCompensationAmt>0</OtherCompensationAmt>
      </Form990PartVIISectionAGrp>
      <Form990PartVIISectionAGrp>
        <PersonNm>ARTHUR F EDDY DMD</PersonNm>
        <TitleTxt>TRUSTEE</TitleTxt>
        <AverageHoursPerWeekRt>4.00</AverageHoursPerWeekRt>
        <AverageHoursPerWeekRltdOrgRt>1.00</AverageHoursPerWeekRltdOrgRt>
        <IndividualTrusteeOrDirectorInd>X</IndividualTrusteeOrDirectorInd>
        <ReportableCompFromOrgAmt>0</ReportableCompFromOrgAmt>
        <ReportableCompFromRltdOrgAmt>0</ReportableCompFromRltdOrgAmt>
        <OtherCompensationAmt>0</OtherCompensationAmt>
      </Form990PartVIISectionAGrp>
      <Form990PartVIISectionAGrp>
        <PersonNm>JEFFREY LOWENSTEIN DMD</PersonNm>
        <TitleTxt>TRUSTEE</TitleTxt>
        <AverageHoursPerWeekRt>4.00</AverageHoursPerWeekRt>
        <AverageHoursPerWeekRltdOrgRt>1.00</AverageHoursPerWeekRltdOrgRt>
        <IndividualTrusteeOrDirectorInd>X</IndividualTrusteeOrDirectorInd>
        <ReportableCompFromOrgAmt>0</ReportableCompFromOrgAmt>
        <ReportableCompFromRltdOrgAmt>0</ReportableCompFromRltdOrgAmt>
        <OtherCompensationAmt>0</OtherCompensationAmt>
      </Form990PartVIISectionAGrp>
      <Form990PartVIISectionAGrp>
        <PersonNm>JOHN P GUSHA DMD</PersonNm>
        <TitleTxt>TRUSTEE</TitleTxt>
        <AverageHoursPerWeekRt>4.00</AverageHoursPerWeekRt>
        <AverageHoursPerWeekRltdOrgRt>1.00</AverageHoursPerWeekRltdOrgRt>
        <IndividualTrusteeOrDirectorInd>X</IndividualTrusteeOrDirectorInd>
        <ReportableCompFromOrgAmt>0</ReportableCompFromOrgAmt>
        <ReportableCompFromRltdOrgAmt>0</ReportableCompFromRltdOrgAmt>
        <OtherCompensationAmt>0</OtherCompensationAmt>
      </Form990PartVIISectionAGrp>
      <TotalReportableCompFromOrgAmt>659546</TotalReportableCompFromOrgAmt>
      <TotReportableCompRltdOrgAmt>0</TotReportableCompRltdOrgAmt>
      <TotalOtherCompensationAmt>70865</TotalOtherCompensationAmt>
      <IndivRcvdGreaterThan100KCnt>3</IndivRcvdGreaterThan100KCnt>
      <FormerOfcrEmployeesListedInd>0</FormerOfcrEmployeesListedInd>
      <TotalCompGreaterThan150KInd>1</TotalCompGreaterThan150KInd>
      <CompensationFromOtherSrcsInd>0</CompensationFromOtherSrcsInd>
      <ContractorCompensationGrp>
        <ContractorName>
          <BusinessName>
            <BusinessNameLine1Txt>MASSACHUSETTS CONVENTION CENTER AUTHORIT</BusinessNameLine1Txt>
          </BusinessName>
        </ContractorName>
        <ContractorAddress>
          <USAddress>
            <AddressLine1Txt>415 SUMMER STREET</AddressLine1Txt>
            <CityNm>BOSTON</CityNm>
            <StateAbbreviationCd>MA</StateAbbreviationCd>
            <ZIPCd>02110</ZIPCd>
          </USAddress>
        </ContractorAddress>
        <ServicesDesc>SPACE RENTAL</ServicesDesc>
        <CompensationAmt>463971</CompensationAmt>
      </ContractorCompensationGrp>
      <ContractorCompensationGrp>
        <ContractorName>
          <BusinessName>
            <BusinessNameLine1Txt>PROJECTION PRESENTATION TECHNOLOGY</BusinessNameLine1Txt>
          </BusinessName>
        </ContractorName>
        <ContractorAddress>
          <USAddress>
            <AddressLine1Txt>415 SUMMER STREET</AddressLine1Txt>
            <CityNm>BOSTON</CityNm>
            <StateAbbreviationCd>MA</StateAbbreviationCd>
            <ZIPCd>02110</ZIPCd>
          </USAddress>
        </ContractorAddress>
        <ServicesDesc>AUDIO/VISUAL SERVICES</ServicesDesc>
        <CompensationAmt>348011</CompensationAmt>
      </ContractorCompensationGrp>
      <ContractorCompensationGrp>
        <ContractorName>
          <BusinessName>
            <BusinessNameLine1Txt>GOULSTON &amp; STORRS</BusinessNameLine1Txt>
          </BusinessName>
        </ContractorName>
        <ContractorAddress>
          <USAddress>
            <AddressLine1Txt>400 ATLANTIC AVE</AddressLine1Txt>
            <CityNm>BOSTON</CityNm>
            <StateAbbreviationCd>MA</StateAbbreviationCd>
            <ZIPCd>02110</ZIPCd>
          </USAddress>
        </ContractorAddress>
        <ServicesDesc>LEGAL SERVICES</ServicesDesc>
        <CompensationAmt>324922</CompensationAmt>
      </ContractorCompensationGrp>
      <ContractorCompensationGrp>
        <ContractorName>
          <BusinessName>
            <BusinessNameLine1Txt>LEVY PREMIUM FOOD SERVICE</BusinessNameLine1Txt>
          </BusinessName>
        </ContractorName>
        <ContractorAddress>
          <USAddress>
            <AddressLine1Txt>415 SUMMER STREET</AddressLine1Txt>
            <CityNm>BOSTON</CityNm>
            <StateAbbreviationCd>MA</StateAbbreviationCd>
            <ZIPCd>02110</ZIPCd>
          </USAddress>
        </ContractorAddress>
        <ServicesDesc>CATERING SERVICES</ServicesDesc>
        <CompensationAmt>267364</CompensationAmt>
      </ContractorCompensationGrp>
      <ContractorCompensationGrp>
        <ContractorName>
          <BusinessName>
            <BusinessNameLine1Txt>SEAPORT HOTEL AT THE WORLD TRADE CTR</BusinessNameLine1Txt>
          </BusinessName>
        </ContractorName>
        <ContractorAddress>
          <USAddress>
            <AddressLine1Txt>200 SEAPORT BLVD SUITE 50</AddressLine1Txt>
            <CityNm>BOSTON</CityNm>
            <StateAbbreviationCd>MA</StateAbbreviationCd>
            <ZIPCd>02110</ZIPCd>
          </USAddress>
        </ContractorAddress>
        <ServicesDesc>HOTEL SERVICES</ServicesDesc>
        <CompensationAmt>153772</CompensationAmt>
      </ContractorCompensationGrp>
      <CntrctRcvdGreaterThan100KCnt>5</CntrctRcvdGreaterThan100KCnt>
      <ProgramServiceRevenueGrp>
        <Desc>YANKEE DENTAL CONGRESS</Desc>
        <BusinessCd>900099</BusinessCd>
        <TotalRevenueColumnAmt>6422835</TotalRevenueColumnAmt>
        <RelatedOrExemptFuncIncomeAmt>6364285</RelatedOrExemptFuncIncomeAmt>
        <UnrelatedBusinessRevenueAmt>58550</UnrelatedBusinessRevenueAmt>
      </ProgramServiceRevenueGrp>
      <ProgramServiceRevenueGrp>
        <Desc>MEMBERSHIP DUES</Desc>
        <BusinessCd>900099</BusinessCd>
        <TotalRevenueColumnAmt>2009030</TotalRevenueColumnAmt>
        <RelatedOrExemptFuncIncomeAmt>2009030</RelatedOrExemptFuncIncomeAmt>
      </ProgramServiceRevenueGrp>
      <ProgramServiceRevenueGrp>
        <Desc>CONTINUING EDUCATION</Desc>
        <BusinessCd>900099</BusinessCd>
        <TotalRevenueColumnAmt>195461</TotalRevenueColumnAmt>
        <RelatedOrExemptFuncIncomeAmt>195461</RelatedOrExemptFuncIncomeAmt>
      </ProgramServiceRevenueGrp>
      <ProgramServiceRevenueGrp>
        <Desc>CONFERENCES AND WORKSHOPS</Desc>
        <BusinessCd>900099</BusinessCd>
        <TotalRevenueColumnAmt>149689</TotalRevenueColumnAmt>
        <RelatedOrExemptFuncIncomeAmt>149689</RelatedOrExemptFuncIncomeAmt>
      </ProgramServiceRevenueGrp>
      <ProgramServiceRevenueGrp>
        <Desc>ADVERTISING</Desc>
        <BusinessCd>541800</BusinessCd>
        <TotalRevenueColumnAmt>93126</TotalRevenueColumnAmt>
        <UnrelatedBusinessRevenueAmt>93126</UnrelatedBusinessRevenueAmt>
      </ProgramServiceRevenueGrp>
      <TotalProgramServiceRevenueAmt>8870141</TotalProgramServiceRevenueAmt>
      <InvestmentIncomeGrp>
        <TotalRevenueColumnAmt>179133</TotalRevenueColumnAmt>
        <ExclusionAmt>179133</ExclusionAmt>
      </InvestmentIncomeGrp>
      <RoyaltiesRevenueGrp>
        <TotalRevenueColumnAmt>205706</TotalRevenueColumnAmt>
        <ExclusionAmt>205706</ExclusionAmt>
      </RoyaltiesRevenueGrp>
      <GrossRentsGrp>
        <RealAmt>347537</RealAmt>
      </GrossRentsGrp>
      <LessRentalExpensesGrp>
        <RealAmt>392771</RealAmt>
      </LessRentalExpensesGrp>
      <RentalIncomeOrLossGrp>
        <RealAmt>-45234</RealAmt>
      </RentalIncomeOrLossGrp>
      <NetRentalIncomeOrLossGrp>
        <TotalRevenueColumnAmt>-45234</TotalRevenueColumnAmt>
        <UnrelatedBusinessRevenueAmt>-13607</UnrelatedBusinessRevenueAmt>
        <ExclusionAmt>-31627</ExclusionAmt>
      </NetRentalIncomeOrLossGrp>
      <GrossAmountSalesAssetsGrp>
        <SecuritiesAmt>2785549</SecuritiesAmt>
      </GrossAmountSalesAssetsGrp>
      <LessCostOthBasisSalesExpnssGrp>
        <SecuritiesAmt>2477111</SecuritiesAmt>
      </LessCostOthBasisSalesExpnssGrp>
      <GainOrLossGrp>
        <SecuritiesAmt>308438</SecuritiesAmt>
      </GainOrLossGrp>
      <NetGainOrLossInvestmentsGrp>
        <TotalRevenueColumnAmt>308438</TotalRevenueColumnAmt>
        <ExclusionAmt>308438</ExclusionAmt>
      </NetGainOrLossInvestmentsGrp>
      <OtherRevenueMiscGrp>
        <Desc>MANAGEMENT FEE</Desc>
        <BusinessCd>900099</BusinessCd>
        <TotalRevenueColumnAmt>57041</TotalRevenueColumnAmt>
        <RelatedOrExemptFuncIncomeAmt>57041</RelatedOrExemptFuncIncomeAmt>
      </OtherRevenueMiscGrp>
      <OtherRevenueMiscGrp>
        <Desc>MISCELLANEOUS</Desc>
        <BusinessCd>900099</BusinessCd>
        <TotalRevenueColumnAmt>25478</TotalRevenueColumnAmt>
        <RelatedOrExemptFuncIncomeAmt>25478</RelatedOrExemptFuncIncomeAmt>
      </OtherRevenueMiscGrp>
      <OtherRevenueTotalAmt>82519</OtherRevenueTotalAmt>
      <TotalRevenueGrp>
        <TotalRevenueColumnAmt>9600703</TotalRevenueColumnAmt>
        <RelatedOrExemptFuncIncomeAmt>8800984</RelatedOrExemptFuncIncomeAmt>
        <UnrelatedBusinessRevenueAmt>138069</UnrelatedBusinessRevenueAmt>
        <ExclusionAmt>661650</ExclusionAmt>
      </TotalRevenueGrp>
      <GrantsToDomesticOrgsGrp>
        <TotalAmt>62900</TotalAmt>
      </GrantsToDomesticOrgsGrp>
      <CompCurrentOfcrDirectorsGrp>
        <TotalAmt>672907</TotalAmt>
      </CompCurrentOfcrDirectorsGrp>
      <OtherSalariesAndWagesGrp>
        <TotalAmt>2554666</TotalAmt>
      </OtherSalariesAndWagesGrp>
      <PensionPlanContributionsGrp>
        <TotalAmt>133955</TotalAmt>
      </PensionPlanContributionsGrp>
      <OtherEmployeeBenefitsGrp>
        <TotalAmt>257282</TotalAmt>
      </OtherEmployeeBenefitsGrp>
      <PayrollTaxesGrp>
        <TotalAmt>244611</TotalAmt>
      </PayrollTaxesGrp>
      <FeesForServicesLegalGrp>
        <TotalAmt>336164</TotalAmt>
      </FeesForServicesLegalGrp>
      <FeesForServicesAccountingGrp>
        <TotalAmt>63100</TotalAmt>
      </FeesForServicesAccountingGrp>
      <OfficeExpensesGrp>
        <TotalAmt>241391</TotalAmt>
      </OfficeExpensesGrp>
      <InformationTechnologyGrp>
        <TotalAmt>198178</TotalAmt>
      </InformationTechnologyGrp>
      <OccupancyGrp>
        <TotalAmt>103997</TotalAmt>
      </OccupancyGrp>
      <TravelGrp>
        <TotalAmt>23940</TotalAmt>
      </TravelGrp>
      <ConferencesMeetingsGrp>
        <TotalAmt>2700669</TotalAmt>
      </ConferencesMeetingsGrp>
      <InterestGrp>
        <TotalAmt>22295</TotalAmt>
      </InterestGrp>
      <DepreciationDepletionGrp>
        <TotalAmt>351285</TotalAmt>
      </DepreciationDepletionGrp>
      <InsuranceGrp>
        <TotalAmt>27997</TotalAmt>
      </InsuranceGrp>
      <OtherExpensesGrp>
        <Desc>OTHER</Desc>
        <TotalAmt>1071348</TotalAmt>
      </OtherExpensesGrp>
      <OtherExpensesGrp>
        <Desc>SEMINARS AND WORKSHOPS</Desc>
        <TotalAmt>362185</TotalAmt>
      </OtherExpensesGrp>
      <OtherExpensesGrp>
        <Desc>BANK FEES</Desc>
        <TotalAmt>233419</TotalAmt>
      </OtherExpensesGrp>
      <OtherExpensesGrp>
        <Desc>PUBLIC AWARENESS PROGRA</Desc>
        <TotalAmt>4479</TotalAmt>
      </OtherExpensesGrp>
      <AllOtherExpensesGrp>
        <TotalAmt>669</TotalAmt>
      </AllOtherExpensesGrp>
      <TotalFunctionalExpensesGrp>
        <TotalAmt>9667437</TotalAmt>
      </TotalFunctionalExpensesGrp>
      <CashNonInterestBearingGrp>
        <BOYAmt>1173448</BOYAmt>
        <EOYAmt>2708814</EOYAmt>
      </CashNonInterestBearingGrp>
      <AccountsReceivableGrp>
        <BOYAmt>1534358</BOYAmt>
        <EOYAmt>1403557</EOYAmt>
      </AccountsReceivableGrp>
      <PrepaidExpensesDefrdChargesGrp>
        <BOYAmt>507577</BOYAmt>
        <EOYAmt>433704</EOYAmt>
      </PrepaidExpensesDefrdChargesGrp>
      <LandBldgEquipCostOrOtherBssAmt>9702516</LandBldgEquipCostOrOtherBssAmt>
      <LandBldgEquipAccumDeprecAmt>4728999</LandBldgEquipAccumDeprecAmt>
      <LandBldgEquipBasisNetGrp>
        <BOYAmt>5338557</BOYAmt>
        <EOYAmt>4973517</EOYAmt>
      </LandBldgEquipBasisNetGrp>
      <InvestmentsPubTradedSecGrp>
        <BOYAmt>8714578</BOYAmt>
        <EOYAmt>8600711</EOYAmt>
      </InvestmentsPubTradedSecGrp>
      <InvestmentsOtherSecuritiesGrp>
        <BOYAmt>371467</BOYAmt>
        <EOYAmt>370798</EOYAmt>
      </InvestmentsOtherSecuritiesGrp>
      <TotalAssetsGrp>
        <BOYAmt>17639985</BOYAmt>
        <EOYAmt>18491101</EOYAmt>
      </TotalAssetsGrp>
      <AccountsPayableAccrExpnssGrp>
        <BOYAmt>941444</BOYAmt>
        <EOYAmt>2608478</EOYAmt>
      </AccountsPayableAccrExpnssGrp>
      <DeferredRevenueGrp>
        <BOYAmt>3678181</BOYAmt>
        <EOYAmt>3611092</EOYAmt>
      </DeferredRevenueGrp>
      <MortgNotesPyblScrdInvstPropGrp>
        <BOYAmt>1695064</BOYAmt>
        <EOYAmt>961892</EOYAmt>
      </MortgNotesPyblScrdInvstPropGrp>
      <OtherLiabilitiesGrp>
        <BOYAmt>553169</BOYAmt>
        <EOYAmt>602062</EOYAmt>
      </OtherLiabilitiesGrp>
      <TotalLiabilitiesGrp>
        <BOYAmt>6867858</BOYAmt>
        <EOYAmt>7783524</EOYAmt>
      </TotalLiabilitiesGrp>
      <OrganizationFollowsSFAS117Ind>X</OrganizationFollowsSFAS117Ind>
      <UnrestrictedNetAssetsGrp>
        <BOYAmt>10772127</BOYAmt>
        <EOYAmt>10707577</EOYAmt>
      </UnrestrictedNetAssetsGrp>
      <TotalNetAssetsFundBalanceGrp>
        <BOYAmt>10772127</BOYAmt>
        <EOYAmt>10707577</EOYAmt>
      </TotalNetAssetsFundBalanceGrp>
      <TotLiabNetAssetsFundBalanceGrp>
        <BOYAmt>17639985</BOYAmt>
        <EOYAmt>18491101</EOYAmt>
      </TotLiabNetAssetsFundBalanceGrp>
      <ReconcilationRevenueExpnssAmt>-66734</ReconcilationRevenueExpnssAmt>
      <NetUnrlzdGainsLossesInvstAmt>2184</NetUnrlzdGainsLossesInvstAmt>
      <OtherChangesInNetAssetsAmt>0</OtherChangesInNetAssetsAmt>
      <InfoInScheduleOPartXIIInd>X</InfoInScheduleOPartXIIInd>
      <MethodOfAccountingAccrualInd>X</MethodOfAccountingAccrualInd>
      <AccountantCompileOrReviewInd>0</AccountantCompileOrReviewInd>
      <FSAuditedInd>1</FSAuditedInd>
      <FSAuditedBasisGrp>
        <ConsolidatedBasisFinclStmtInd>X</ConsolidatedBasisFinclStmtInd>
      </FSAuditedBasisGrp>
      <AuditCommitteeInd>1</AuditCommitteeInd>
      <FederalGrantAuditRequiredInd>0</FederalGrantAuditRequiredInd>
    </IRS990>
    <IRS990ScheduleC documentId="RetDoc1039700001">
      <SubstantiallyAllDuesNondedInd>0</SubstantiallyAllDuesNondedInd>
      <OnlyInHouseLobbyingInd>0</OnlyInHouseLobbyingInd>
      <AgreeCarryoverPriorYearInd>0</AgreeCarryoverPriorYearInd>
      <DuesAssessmentsAmt>1724798</DuesAssessmentsAmt>
      <NonDeductibleLbbyngPltclCYAmt>471864</NonDeductibleLbbyngPltclCYAmt>
      <NonDeductibleLbbyngPltclTotAmt>471864</NonDeductibleLbbyngPltclTotAmt>
      <AggregateReportedDuesNtcAmt>471864</AggregateReportedDuesNtcAmt>
    </IRS990ScheduleC>
    <IRS990ScheduleD documentId="RetDoc1040000001">
      <LandGrp>
        <OtherCostOrOtherBasisAmt>925873</OtherCostOrOtherBasisAmt>
        <BookValueAmt>925873</BookValueAmt>
      </LandGrp>
      <BuildingsGrp>
        <OtherCostOrOtherBasisAmt>5457456</OtherCostOrOtherBasisAmt>
        <DepreciationAmt>2083185</DepreciationAmt>
        <BookValueAmt>3374271</BookValueAmt>
      </BuildingsGrp>
      <LeaseholdImprovementsGrp>
        <OtherCostOrOtherBasisAmt>383784</OtherCostOrOtherBasisAmt>
        <DepreciationAmt>174385</DepreciationAmt>
        <BookValueAmt>209399</BookValueAmt>
      </LeaseholdImprovementsGrp>
      <EquipmentGrp>
        <OtherCostOrOtherBasisAmt>1499646</OtherCostOrOtherBasisAmt>
        <DepreciationAmt>1035672</DepreciationAmt>
        <BookValueAmt>463974</BookValueAmt>
      </EquipmentGrp>
      <OtherLandBuildingsGrp>
        <OtherCostOrOtherBasisAmt>1435757</OtherCostOrOtherBasisAmt>
        <DepreciationAmt>1435757</DepreciationAmt>
        <BookValueAmt>0</BookValueAmt>
      </OtherLandBuildingsGrp>
      <TotalBookValueLandBuildingsAmt>4973517</TotalBookValueLandBuildingsAmt>
      <OtherLiabilitiesOrgGrp>
        <Desc>DUE TO RELATED PARTY</Desc>
        <Amt>345000</Amt>
      </OtherLiabilitiesOrgGrp>
      <OtherLiabilitiesOrgGrp>
        <Desc>MISCELLANEOUS</Desc>
        <Amt>257062</Amt>
      </OtherLiabilitiesOrgGrp>
      <TotalLiabilityAmt>602062</TotalLiabilityAmt>
      <FootnoteTextInd>X</FootnoteTextInd>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>PART X, LINE 2:</FormAndLineReferenceDesc>
        <ExplanationTxt>MDS AND AFFILIATES ACCOUNT FOR UNCERTAINTY IN INCOME TAXES IN ACCORDANCE WITH ASC TOPIC, INCOME TAXES. THIS STANDARD CLARIFIES THE ACCOUNTING FOR UNCERTAINTY IN TAX POSITIONS AND PRESCRIBES A RECOGNITION THRESHOLD AND MEASUREMENT ATTRIBUTE FOR THE CONSOLIDATED FINANCIAL STATEMENTS REGARDING A TAX POSITION TAKEN OR EXPECTED TO BE TAKEN IN A TAX RETURN. MDS AND AFFILIATES HAVE DETERMINED THAT THERE ARE NO UNCERTAIN TAX POSITIONS WHICH QUALIFY FOR EITHER RECOGNITION OR DISCLOSURE IN THE CONSOLIDATED FINANCIAL STATEMENTS AT JUNE 30, 2019. MDS AND AFFILIATES' INFORMATION RETURNS ARE SUBJECT TO EXAMINATION BY THE FEDERAL AND STATE JURISDICTIONS.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleD>
    <IRS990ScheduleI documentId="RetDoc1041900001">
      <GrantRecordsMaintainedInd>1</GrantRecordsMaintainedInd>
      <RecipientTable>
        <RecipientBusinessName>
          <BusinessNameLine1Txt>DCD (DOCTORS CARING FOR DOCTORS)</BusinessNameLine1Txt>
        </RecipientBusinessName>
        <USAddress>
          <AddressLine1Txt>PO BOX 716</AddressLine1Txt>
          <CityNm>ANDOVER</CityNm>
          <StateAbbreviationCd>MA</StateAbbreviationCd>
          <ZIPCd>01810</ZIPCd>
        </USAddress>
        <IRCSectionDesc>170(B)(1)(A)(V)</IRCSectionDesc>
        <CashGrantAmt>62900</CashGrantAmt>
        <PurposeOfGrantTxt>THESE GRANT MONIES SUPPORT THE ACTIVITIES OF THAT ORGANIZATION THAT WORKS IN CONJUNCTION WITH THE MDS WELL-BEING COMMITTEE. MDS HAS PAID OUT THIS GRANT FOR MANY YEARS AND IT IS PAID IN EQUAL MONTHLY INSTALLMENTS OVER THE COURSE OF THE FISCAL YEAR.</PurposeOfGrantTxt>
      </RecipientTable>
      <Total501c3OrgCnt>1</Total501c3OrgCnt>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>PART I, LINE 2:</FormAndLineReferenceDesc>
        <ExplanationTxt>GRANTS MADE BY MDS AND THE DISTRICTS PROVIDED FUNDING FOR VARIOUS DENTAL PROGRAMS. GRANTEES ARE REQUIRED TO SUBMIT REPORTS DETAILING HOW GRANT FUNDS WERE SPENT.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleI>
    <IRS990ScheduleJ documentId="RetDoc1042400001">
      <WrittenEmploymentContractInd>X</WrittenEmploymentContractInd>
      <BoardOrCommitteeApprovalInd>X</BoardOrCommitteeApprovalInd>
      <SeverancePaymentInd>0</SeverancePaymentInd>
      <SupplementalNonqualRtrPlanInd>1</SupplementalNonqualRtrPlanInd>
      <EquityBasedCompArrngmInd>0</EquityBasedCompArrngmInd>
      <RltdOrgOfficerTrstKeyEmplGrp>
        <PersonNm>ROBERT BOOSE</PersonNm>
        <TitleTxt>EXECUTIVE DIRECTOR</TitleTxt>
        <BaseCompensationFilingOrgAmt>330423</BaseCompensationFilingOrgAmt>
        <CompensationBasedOnRltdOrgsAmt>0</CompensationBasedOnRltdOrgsAmt>
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        <TotalCompensationRltdOrgsAmt>0</TotalCompensationRltdOrgsAmt>
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        <PersonNm>KATHLEEN BOYCE</PersonNm>
        <TitleTxt>CFO/COO</TitleTxt>
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        <BonusFilingOrganizationAmount>0</BonusFilingOrganizationAmount>
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        <OtherCompensationFilingOrgAmt>0</OtherCompensationFilingOrgAmt>
        <OtherCompensationRltdOrgsAmt>0</OtherCompensationRltdOrgsAmt>
        <DeferredCompensationFlngOrgAmt>0</DeferredCompensationFlngOrgAmt>
        <DeferredCompRltdOrgsAmt>0</DeferredCompRltdOrgsAmt>
        <NontaxableBenefitsFilingOrgAmt>19446</NontaxableBenefitsFilingOrgAmt>
        <NontaxableBenefitsRltdOrgsAmt>0</NontaxableBenefitsRltdOrgsAmt>
        <TotalCompensationFilingOrgAmt>241892</TotalCompensationFilingOrgAmt>
        <TotalCompensationRltdOrgsAmt>0</TotalCompensationRltdOrgsAmt>
        <CompReportPrior990FilingOrgAmt>0</CompReportPrior990FilingOrgAmt>
        <CompReportPrior990RltdOrgsAmt>0</CompReportPrior990RltdOrgsAmt>
      </RltdOrgOfficerTrstKeyEmplGrp>
    </IRS990ScheduleJ>
    <IRS990ScheduleO documentId="RetDoc1044400001">
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION A, LINE 6</FormAndLineReferenceDesc>
        <ExplanationTxt>THE ORGANIZATION'S MEMBERSHIP IS COMPRISED OF ORAL HEALTH CARE PROFESSIONALS IN MASSACHUSETTS.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION A, LINE 7A</FormAndLineReferenceDesc>
        <ExplanationTxt>THE ORGANIZATION'S MEMBERS ELECT THE DELEGATES, WHO REPRESENT THEM IN VOTING TO ELECT THE GOVERNING BODY, THE BOARD OF TRUSTEES.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION A, LINE 7B</FormAndLineReferenceDesc>
        <ExplanationTxt>THE ANNUAL MEETING OF DELEGATES HAS THE RIGHT TO ADDRESS ANY ITEMS OR ACTIONS TAKEN BY THE BOARD DURING THE YEAR.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 11B</FormAndLineReferenceDesc>
        <ExplanationTxt>THE FORM 990 IS PROVIDED TO THE TRUSTEES BEFORE FILING. THE EXECUTIVE DIRECTOR REVIEWS THE RETURN PRIOR TO BEING FILED.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 12C</FormAndLineReferenceDesc>
        <ExplanationTxt>ALL BOARD MEMBERS SIGN THE CONFLICT OF INTEREST POLICY AND ANY CONFLICTS ARE ANNOUNCED AT THE BEGINNING OF EACH BOARD MEETING.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 15</FormAndLineReferenceDesc>
        <ExplanationTxt>THE EXECUTIVE DIRECTOR'S COMPENSATION IS DETERMINED BY THE COMPENSATION COMMITTEE OF THE BOARD OF TRUSTEES. ALL OTHER OFFICERS AND KEY EMPLOYEES' SALARIES ARE DETERMINED BY THE EXECUTIVE DIRECTOR.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION C, LINE 19</FormAndLineReferenceDesc>
        <ExplanationTxt>THE ORGANIZATION MAKES ITS GOVERNING DOCUMENTS, CONFLICT OF INTEREST POLICY AND FINANCIAL STATEMENTS AVAILABLE TO THE PUBLIC UPON REQUEST.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART XII, LINE 2C:</FormAndLineReferenceDesc>
        <ExplanationTxt>THIS PROCESS HAS NOT CHANGED FROM THE PRIOR YEAR.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleO>
    <IRS990ScheduleR documentId="RetDoc1043400001">
      <IdDisregardedEntitiesGrp>
        <DisregardedEntityName>
          <BusinessNameLine1Txt>FIRMIN JOINT VENTURE LLC</BusinessNameLine1Txt>
        </DisregardedEntityName>
        <USAddress>
          <AddressLine1Txt>TWO WILLOW STREET SUITE 200</AddressLine1Txt>
          <CityNm>SOUTHBOROUGH</CityNm>
          <StateAbbreviationCd>MA</StateAbbreviationCd>
          <ZIPCd>01745</ZIPCd>
        </USAddress>
        <EIN>043446721</EIN>
        <PrimaryActivitiesTxt>TO OWN MDS' PRINCIPAL PROPERTY</PrimaryActivitiesTxt>
        <LegalDomicileStateCd>MA</LegalDomicileStateCd>
        <TotalIncomeAmt>715829</TotalIncomeAmt>
        <EndOfYearAssetsAmt>4616675</EndOfYearAssetsAmt>
        <DirectControllingEntityName>
          <BusinessNameLine1Txt>MASSACHUSETTS DENTAL SOCIETY</BusinessNameLine1Txt>
        </DirectControllingEntityName>
      </IdDisregardedEntitiesGrp>
      <IdRelatedTaxExemptOrgGrp>
        <DisregardedEntityName>
          <BusinessNameLine1Txt>MDS FOUNDATION INC</BusinessNameLine1Txt>
        </DisregardedEntityName>
        <USAddress>
          <AddressLine1Txt>TWO WILLOW STREET SUITE 200</AddressLine1Txt>
          <CityNm>SOUTHBOROUGH</CityNm>
          <StateAbbreviationCd>MA</StateAbbreviationCd>
          <ZIPCd>01715</ZIPCd>
        </USAddress>
        <EIN>043466040</EIN>
        <PrimaryActivitiesTxt>IMPROVE ORAL HEALTH CARE OF MASSACHUSETTS RESIDENTS</PrimaryActivitiesTxt>
        <LegalDomicileStateCd>MA</LegalDomicileStateCd>
        <ExemptCodeSectionTxt>501(C)(3)</ExemptCodeSectionTxt>
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        <DisregardedEntityName>
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        </DisregardedEntityName>
        <USAddress>
          <AddressLine1Txt>TWO WILLOW STREET SUITE 200</AddressLine1Txt>
          <CityNm>SOUTHBOROUGH</CityNm>
          <StateAbbreviationCd>MA</StateAbbreviationCd>
          <ZIPCd>01715</ZIPCd>
        </USAddress>
        <EIN>046139122</EIN>
        <PrimaryActivitiesTxt>HELP DENTISTS IN NEED</PrimaryActivitiesTxt>
        <LegalDomicileStateCd>MA</LegalDomicileStateCd>
        <ExemptCodeSectionTxt>501(C)(3)</ExemptCodeSectionTxt>
        <PublicCharityStatusTxt>LINE 12A, I</PublicCharityStatusTxt>
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      <IdRelatedOrgTxblCorpTrGrp>
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          <BusinessNameLine1Txt>MDS INSURANCE SERVICES INC</BusinessNameLine1Txt>
        </RelatedOrganizationName>
        <USAddress>
          <AddressLine1Txt>TWO WILLOW STREET SUITE 200</AddressLine1Txt>
          <CityNm>SOUTHBOROUGH</CityNm>
          <StateAbbreviationCd>MA</StateAbbreviationCd>
          <ZIPCd>01745</ZIPCd>
        </USAddress>
        <EIN>043432374</EIN>
        <PrimaryActivitiesTxt>INSURANCE AGENT</PrimaryActivitiesTxt>
        <LegalDomicileStateCd>MA</LegalDomicileStateCd>
        <DirectControllingEntityName>
          <BusinessNameLine1Txt>MASSACHUSETTS DENTAL SOCIETY</BusinessNameLine1Txt>
        </DirectControllingEntityName>
        <EntityTypeTxt>C</EntityTypeTxt>
        <ShareOfTotalIncomeAmt>15613</ShareOfTotalIncomeAmt>
        <ShareOfEOYAssetsAmt>373235</ShareOfEOYAssetsAmt>
        <OwnershipPct>1.00000</OwnershipPct>
        <ControlledOrganizationInd>0</ControlledOrganizationInd>
      </IdRelatedOrgTxblCorpTrGrp>
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      <GiftGrntOrCapContriToOthOrgInd>0</GiftGrntOrCapContriToOthOrgInd>
      <GiftGrntCapContriFromOthOrgInd>0</GiftGrntCapContriFromOthOrgInd>
      <LoansOrGuaranteesToOtherOrgInd>0</LoansOrGuaranteesToOtherOrgInd>
      <LoansOrGuaranteesFromOthOrgInd>0</LoansOrGuaranteesFromOthOrgInd>
      <DivRelatedOrganizationInd>0</DivRelatedOrganizationInd>
      <AssetSaleToOtherOrgInd>0</AssetSaleToOtherOrgInd>
      <AssetPurchaseFromOtherOrgInd>0</AssetPurchaseFromOtherOrgInd>
      <AssetExchangeInd>0</AssetExchangeInd>
      <RentalOfFacilitiesToOthOrgInd>0</RentalOfFacilitiesToOthOrgInd>
      <RentalOfFcltsFromOthOrgInd>0</RentalOfFcltsFromOthOrgInd>
      <PerformOfServicesForOthOrgInd>0</PerformOfServicesForOthOrgInd>
      <PerformOfServicesByOtherOrgInd>0</PerformOfServicesByOtherOrgInd>
      <SharingOfFacilitiesInd>0</SharingOfFacilitiesInd>
      <PaidEmployeesSharingInd>0</PaidEmployeesSharingInd>
      <ReimbursementPaidToOtherOrgInd>0</ReimbursementPaidToOtherOrgInd>
      <ReimbursementPaidByOtherOrgInd>1</ReimbursementPaidByOtherOrgInd>
      <TransferToOtherOrgInd>0</TransferToOtherOrgInd>
      <TransferFromOtherOrgInd>0</TransferFromOtherOrgInd>
      <TransactionsRelatedOrgGrp>
        <OtherOrganizationName>
          <BusinessNameLine1Txt>MDS INSURANCE SERVICES INC</BusinessNameLine1Txt>
        </OtherOrganizationName>
        <TransactionTypeTxt>Q</TransactionTypeTxt>
        <InvolvedAmt>345000</InvolvedAmt>
        <MethodOfAmountDeterminationTxt>AMOUNT DUE TO MDSIS</MethodOfAmountDeterminationTxt>
      </TransactionsRelatedOrgGrp>
    </IRS990ScheduleR>
  </ReturnData>
</Return>