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  <xs:element id="inbk_Plan2013Member" abstract="true" name="Plan2013Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_DeferredStockRelatedToDirectorsDeferredStockPlanOutstandingNumber" abstract="false" name="DeferredStockRelatedToDirectorsDeferredStockPlanOutstandingNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="inbk_DeferredStockRelatedToDirectorsDeferredStockPlanGrantedInPeriod" abstract="false" name="DeferredStockRelatedToDirectorsDeferredStockPlanGrantedInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="inbk_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesOutstanding" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesOutstanding" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="inbk_CommonStockSharesReservedForFutureGrants" abstract="false" name="CommonStockSharesReservedForFutureGrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="inbk_SharebasedCompensationArrangementbySharebasePaymentAwardPercentageofAnnualRetainerReceivedinCommonStockorDeferredStockRights" abstract="false" name="SharebasedCompensationArrangementbySharebasePaymentAwardPercentageofAnnualRetainerReceivedinCommonStockorDeferredStockRights" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="inbk_DeferredStockRightConversionToCommonStock" abstract="false" name="DeferredStockRightConversionToCommonStock" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="inbk_InterestRateSwapBackToBackMember" abstract="true" name="InterestRateSwapBackToBackMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_ServicingAssetMember" abstract="true" name="ServicingAssetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_ImpairedLoansMember" abstract="true" name="ImpairedLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_MeasurementInputDiscountForTypeOfPropertyAndCurrentMarketConditionsMember" abstract="true" name="MeasurementInputDiscountForTypeOfPropertyAndCurrentMarketConditionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_MeasurementInputDiscountForCurrentMarketConditionsMember" abstract="true" name="MeasurementInputDiscountForCurrentMarketConditionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_ValuationTechniqueFairValueOfCollateralMember" abstract="true" name="ValuationTechniqueFairValueOfCollateralMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_OtherRealEstateOwnedMember" abstract="true" name="OtherRealEstateOwnedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_ImpairedFinancingReceivableMeasurementInput" abstract="false" name="ImpairedFinancingReceivableMeasurementInput" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="inbk_InterestReceivableAtFairValue" abstract="false" name="InterestReceivableAtFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="inbk_FederalHomeLoanBankStockAtFairValue" abstract="false" name="FederalHomeLoanBankStockAtFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="inbk_InterestPayableAtFairValue" abstract="false" name="InterestPayableAtFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="inbk_BackToBackSwapsMember" abstract="true" name="BackToBackSwapsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_AmortizationExpense" abstract="false" name="AmortizationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="inbk_AOCIGainLossDebtSecuritiesTransferredFromAvailableForSaleToHeldToMaturityMember" abstract="true" name="AOCIGainLossDebtSecuritiesTransferredFromAvailableForSaleToHeldToMaturityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_LocationStatementOfIncomeBalanceAxis" abstract="true" name="LocationStatementOfIncomeBalanceAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="inbk_LocationStatementOfIncomeBalanceDomain" abstract="true" name="LocationStatementOfIncomeBalanceDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_InterestIncomeExpenseOperatingMember" abstract="true" name="InterestIncomeExpenseOperatingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_IncomeBeforeIncomeTaxesMember" abstract="true" name="IncomeBeforeIncomeTaxesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_TaxBenefitMember" abstract="true" name="TaxBenefitMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="inbk_NetIncomeLossAttributableToParentMember" abstract="true" name="NetIncomeLossAttributableToParentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
