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        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:href="stem-20140331_cal.xml" xlink:title="Calculation Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:href="stem-20140331_def.xml" xlink:title="Definition Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:href="stem-20140331_lab.xml" xlink:title="Label Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:href="stem-20140331_pre.xml" xlink:title="Presentation Links, all"/>
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd"/>
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/>
  <import namespace="http://fasb.org/us-types/2013-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2013/elts/us-types-2013-01-31.xsd"/>
  <import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd"/>
  <import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd"/>
  <import namespace="http://fasb.org/us-gaap/2013-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/country/2013-01-31" schemaLocation="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/currency/2012-01-31" schemaLocation="http://xbrl.sec.gov/currency/2012/currency-2012-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/dei/2013-01-31" schemaLocation="http://xbrl.sec.gov/dei/2013/dei-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/exch/2013-01-31" schemaLocation="http://xbrl.sec.gov/exch/2013/exch-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/invest/2013-01-31" schemaLocation="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/stpr/2011-01-31" schemaLocation="http://xbrl.sec.gov/stpr/2011/stpr-2011-01-31.xsd"/>
  <element name="AccretionOfDebtDiscountNetCarryingAmount" id="stem_AccretionOfDebtDiscountNetCarryingAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AddChangeInFairValueOfWarrants" id="stem_AddChangeInFairValueOfWarrants" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AggregateLimitOfSharesIssuableToIncentiveStockOptionAwards" id="stem_AggregateLimitOfSharesIssuableToIncentiveStockOptionAwards" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AmortizationOfDebtDiscountAndDebtIssuanceCosts" id="stem_AmortizationOfDebtDiscountAndDebtIssuanceCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AnnualIncreaseInNumberOfSharesOfCommonStock" id="stem_AnnualIncreaseInNumberOfSharesOfCommonStock" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ApprovalOfFundToCollaborators" id="stem_ApprovalOfFundToCollaborators" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ApprovalOfFundToCollaboratorsMaximumValidationPeriod" id="stem_ApprovalOfFundToCollaboratorsMaximumValidationPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments" id="stem_AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments" id="stem_AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="BmrGatewayBoulevardLlcMember" id="stem_BmrGatewayBoulevardLlcMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="BusinessAcquisitionCostOfAcquiredEntityPurchasePriceNet" id="stem_BusinessAcquisitionCostOfAcquiredEntityPurchasePriceNet" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="BusinessAcquisitionPurchasePriceAllocationsGoodwillAmount" id="stem_BusinessAcquisitionPurchasePriceAllocationsGoodwillAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CaliforniaInstituteForRegenerativeMedicineMember" id="stem_CaliforniaInstituteForRegenerativeMedicineMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CapitalUnitsNumberOfUnitsSoldToInvestors" id="stem_CapitalUnitsNumberOfUnitsSoldToInvestors" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CapitalUnitsPricePerUnit" id="stem_CapitalUnitsPricePerUnit" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CarryingValueOfPurchasedLoans" id="stem_CarryingValueOfPurchasedLoans" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CashAndCashEquivalentsMaturityPeriod" id="stem_CashAndCashEquivalentsMaturityPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ClassOfWarrantOrRightExercisePeriodOfWarrantsOrRights" id="stem_ClassOfWarrantOrRightExercisePeriodOfWarrantsOrRights" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ClassOfWarrantOrRightNumberOfWarrantsOrRightsExercised" id="stem_ClassOfWarrantOrRightNumberOfWarrantsOrRightsExercised" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ClassOfWarrantOrRightNumberOfWarrantsOrRightsExpired" id="stem_ClassOfWarrantOrRightNumberOfWarrantsOrRightsExpired" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ClassOfWarrantOrRightNumberOfWarrantsOrRightsIssued" id="stem_ClassOfWarrantOrRightNumberOfWarrantsOrRightsIssued" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CommitmentAndContingenciesLineItems" id="stem_CommitmentAndContingenciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CommitmentAndContingenciesTable" id="stem_CommitmentAndContingenciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="CommonStockPerUnit" id="stem_CommonStockPerUnit" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ContinuingValueOfPatent" id="stem_ContinuingValueOfPatent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="CustomerRelationshipsAndDevelopedTechnologyMember" id="stem_CustomerRelationshipsAndDevelopedTechnologyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentAmortizedDiscountPercentage" id="stem_DebtInstrumentAmortizedDiscountPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentPeriodDuringWhichLoanIsSubjectToInterestOnlyPayments" id="stem_DebtInstrumentPeriodDuringWhichLoanIsSubjectToInterestOnlyPayments" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentPeriodDuringWhichLoanIsSubjectToPrincipalAndInterestPayments" id="stem_DebtInstrumentPeriodDuringWhichLoanIsSubjectToPrincipalAndInterestPayments" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DecemberTwoThousandElevenFinancingMember" id="stem_DecemberTwoThousandElevenFinancingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DepositsAndOtherLongTermLiabilities" id="stem_DepositsAndOtherLongTermLiabilities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DocumentAndEntityInformationAbstract" id="stem_DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EquityIncentivePlansMember" id="stem_EquityIncentivePlansMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EquityMethodInvestmentsAndCostMethodInvestmentsAbstract" id="stem_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueAllocatedToWarrant" id="stem_FairValueAllocatedToWarrant" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueAssetsMeasuredOnRecurringBasisDirectlyOrIndirectlyObservableInputReconciliationTableTextBlock" id="stem_FairValueAssetsMeasuredOnRecurringBasisDirectlyOrIndirectlyObservableInputReconciliationTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueAssumptionsTableTextBlock" id="stem_FairValueAssumptionsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueMeasurementWithDirectlyOrIndirectlyObservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" id="stem_FairValueMeasurementWithDirectlyOrIndirectlyObservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueMeasurementWithDirectlyOrIndirectlyObservableInputsReconciliationRecurringBasisLiabilitySettlements" id="stem_FairValueMeasurementWithDirectlyOrIndirectlyObservableInputsReconciliationRecurringBasisLiabilitySettlements" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValueCurrent" id="stem_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValueCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValueNoncurrent" id="stem_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValueNoncurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueOfWarrantLiability" id="stem_FairValueOfWarrantLiability" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueOfWarrants" id="stem_FairValueOfWarrants" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsForeignCurrencyTranslation" id="stem_FiniteLivedIntangibleAssetsForeignCurrencyTranslation" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ImpairmentsOfIntangibleAssetFiniteLived" id="stem_ImpairmentsOfIntangibleAssetFiniteLived" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInAccruedInterestAndOtherReceivables" id="stem_IncreaseDecreaseInAccruedInterestAndOtherReceivables" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInAccruedWindDownExpenses" id="stem_IncreaseDecreaseInAccruedWindDownExpenses" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInDeferredRent" id="stem_IncreaseDecreaseInDeferredRent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInFairValueOfWarrant" id="stem_IncreaseDecreaseInFairValueOfWarrant" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InstitutionalInvestorsUnitsCommonStockSharesIssuedPerUnit" id="stem_InstitutionalInvestorsUnitsCommonStockSharesIssuedPerUnit" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InstitutionalInvestorsUnitsWarrantsIssuedPerUnit" id="stem_InstitutionalInvestorsUnitsWarrantsIssuedPerUnit" type="us-types:perUnitItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LoanFees" id="stem_LoanFees" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtBondInterestRate" id="stem_LongTermDebtBondInterestRate" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaturityPeriodOfLongTermDebt" id="stem_MaturityPeriodOfLongTermDebt" type="xbrli:gYearMonthItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MinimumExpirationYearOfIntangibleAssets" id="stem_MinimumExpirationYearOfIntangibleAssets" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NatureOfBusinessPolicyTextBlock" id="stem_NatureOfBusinessPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NovemberTwoThousandEightFinancingMember" id="stem_NovemberTwoThousandEightFinancingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NovemberTwoThousandNineFinancingMember" id="stem_NovemberTwoThousandNineFinancingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfPatientsViolateClaims" id="stem_NumberOfPatientsViolateClaims" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfRestrictedUnitVestOverNextFiscalYear" id="stem_NumberOfRestrictedUnitVestOverNextFiscalYear" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfRestrictedUnitWouldVestOverVestingPeriod" id="stem_NumberOfRestrictedUnitWouldVestOverVestingPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfShareBasedEquityIncentivePlan" id="stem_NumberOfShareBasedEquityIncentivePlan" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfWarrantExercised" id="stem_NumberOfWarrantExercised" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfWarrantUnitSold" id="stem_NumberOfWarrantUnitSold" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OutstandingPrincipalAmountOfLongTermDebt" id="stem_OutstandingPrincipalAmountOfLongTermDebt" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrologisLpMember" id="stem_PrologisLpMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PublicOfferedUnitsSeriesWarrantsIssuedPerUnit" id="stem_PublicOfferedUnitsSeriesWarrantsIssuedPerUnit" type="us-types:perUnitItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedStockThreeMember" id="stem_RestrictedStockThreeMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedStockUnitConversionIntoSharesPeriod" id="stem_RestrictedStockUnitConversionIntoSharesPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedStockUnitsVestedDescriptionAfterSpecifiedPeriod" id="stem_RestrictedStockUnitsVestedDescriptionAfterSpecifiedPeriod" type="xbrli:decimalItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedStockUnitVestDescription" id="stem_RestrictedStockUnitVestDescription" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RevenueFromLicensingAgreementsAndGrants" id="stem_RevenueFromLicensingAgreementsAndGrants" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesAWarrantsMember" id="stem_SeriesAWarrantsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBWarrantMember" id="stem_SeriesBWarrantMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBWarrantsMember" id="stem_SeriesBWarrantsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesWarrantMember" id="stem_SeriesWarrantMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPercentageMonthly" id="stem_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPercentageMonthly" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPercentageYearly" id="stem_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPercentageYearly" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsNonvestedNumber" id="stem_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsNonvestedNumber" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionEquityInstrumentsForfeitures" id="stem_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionEquityInstrumentsForfeitures" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsCancelledInPeriodWeightedAverageGrantDateFairValue" id="stem_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsCancelledInPeriodWeightedAverageGrantDateFairValue" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedInPeriodWeightedAverageGrantDateFairValue" id="stem_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedInPeriodWeightedAverageGrantDateFairValue" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageGrantDateFairValues" id="stem_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageGrantDateFairValues" type="num:perShareItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsVestedInPeriodWeightedAverageExercisePrice" id="stem_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsVestedInPeriodWeightedAverageExercisePrice" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationImpactOnBasicAndDilutedEarningsPerShare" id="stem_ShareBasedCompensationImpactOnBasicAndDilutedEarningsPerShare" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationShareBasedAwardsEmployeeTerminationUnvestedAwardsForfeiturePeriodMaximum" id="stem_ShareBasedCompensationShareBasedAwardsEmployeeTerminationUnvestedAwardsForfeiturePeriodMaximum" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SiliconValleyBankLoanAgreementWarrantMember" id="stem_SiliconValleyBankLoanAgreementWarrantMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SiliconValleyBankMember" id="stem_SiliconValleyBankMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StatementOfComprehensiveIncomeAbstract" id="stem_StatementOfComprehensiveIncomeAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StemCellSciencesUkMember" id="stem_StemCellSciencesUkMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfChangesInFairValueOfWarrantLiabilityTableTextBlock" id="stem_SummaryOfChangesInFairValueOfWarrantLiabilityTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfOutstandingWarrantsAndFairValueOfWarrantLiabilityTableTextBlock" id="stem_SummaryOfOutstandingWarrantsAndFairValueOfWarrantLiabilityTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TermOfOperatingLease" id="stem_TermOfOperatingLease" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnvestedStockOptionsMember" id="stem_UnvestedStockOptionsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantExpiration" id="stem_WarrantExpiration" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantIssuedForWarrantExercised" id="stem_WarrantIssuedForWarrantExercised" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantLiabilityTextBlock" id="stem_WarrantLiabilityTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantsIssuedPerUnit" id="stem_WarrantsIssuedPerUnit" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WindDownExpenses" id="stem_WindDownExpenses" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
