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<?xml version="1.0" encoding="windows-1252"?> |
<!-- DFIN ActiveDisclosure(SM) XBRL Linkbase Document - http://www.dfinsolutions.com/ --> |
<!-- Creation Date : 2021-08-14T00:40:55.4775980+00:00 --> |
<!-- Version : 5.0.1.648 --> |
<!-- Package ID : 578125dbcd604441bacf79287dab033a --> |
<!-- Copyright (c) 2021 Donnelley Financial Solutions, Inc. All Rights Reserved. --> |
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| | <link:loc xlink:href="bioc-20210630.xsd#bioc_AdditionalReservesRelatedToAgedAccountReceivable" xlink:type="locator" xlink:label="bioc_AdditionalReservesRelatedToAgedAccountReceivable"/> |
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| | <link:loc xlink:href="bioc-20210630.xsd#bioc_AmortizationPeriod" xlink:type="locator" xlink:label="bioc_AmortizationPeriod"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RevenuePracticalExpedientRemainingPerformanceObligationDescription" xlink:type="locator" xlink:label="us-gaap_RevenuePracticalExpedientRemainingPerformanceObligationDescription"/> |
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| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockholdersEquityReverseStockSplit" xlink:type="locator" xlink:label="us-gaap_StockholdersEquityReverseStockSplit"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:type="locator" xlink:label="us-gaap_CommonStockSharesAuthorized"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:type="locator" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_RTPCRCoronavirusAidReliefAndEconomicSecurityActNineteenTestingMember" xlink:type="locator" xlink:label="bioc_RTPCRCoronavirusAidReliefAndEconomicSecurityActNineteenTestingMember"/> |
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| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ProductsAndServicesDomain" xlink:type="locator" xlink:label="srt_ProductsAndServicesDomain"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ConcentrationRiskTypeDomain" xlink:to="us-gaap_CustomerConcentrationRiskMember" order="10090.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ConcentrationRiskTable" xlink:to="us-gaap_ConcentrationRiskByBenchmarkAxis" order="10140.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:to="us-gaap_ConcentrationRiskBenchmarkDomain_2" order="10150.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:to="us-gaap_ConcentrationRiskBenchmarkDomain" order="10170.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ConcentrationRiskBenchmarkDomain" xlink:to="us-gaap_SalesRevenueNetMember" order="10190.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ConcentrationRiskTable" xlink:to="us-gaap_LiabilityForCatastropheClaimsByCatastrophicEventAxis" order="10240.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_LiabilityForCatastropheClaimsByCatastrophicEventAxis" xlink:to="us-gaap_CatastrophicEventDomain" order="10270.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CatastrophicEventDomain" xlink:to="bioc_CoronavirusAidReliefAndEconomicSecurityActMember" order="10290.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ConcentrationRiskTable" xlink:to="srt_CounterpartyNameAxis" order="10300.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="srt_CounterpartyNameAxis" xlink:to="srt_RepurchaseAgreementCounterpartyNameDomain_2" order="10310.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_CounterpartyNameAxis" xlink:to="srt_RepurchaseAgreementCounterpartyNameDomain" order="10330.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RepurchaseAgreementCounterpartyNameDomain" xlink:to="bioc_MedicareAndMedicareAdvantageMember" order="10350.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RepurchaseAgreementCounterpartyNameDomain" xlink:to="bioc_BlueCrossBlueShieldMember" order="10370.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RepurchaseAgreementCounterpartyNameDomain" xlink:to="bioc_UnitedHealthcareMember" order="10390.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ConcentrationRiskTypeDomain" xlink:to="us-gaap_CreditConcentrationRiskMember" order="10450.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ConcentrationRiskBenchmarkDomain" xlink:to="us-gaap_AccountsReceivableMember" order="10550.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ConcentrationRiskTable" xlink:to="us-gaap_HealthCareOrganizationRevenueSourcesAxis" order="10660.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_HealthCareOrganizationRevenueSourcesAxis" xlink:to="us-gaap_HealthCareOrganizationRevenueSourcesDomain_2" order="10670.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_HealthCareOrganizationRevenueSourcesAxis" xlink:to="us-gaap_HealthCareOrganizationRevenueSourcesDomain" order="10690.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_HealthCareOrganizationRevenueSourcesDomain" xlink:to="bioc_MedicareAndMedicareAdvantageMember" order="10710.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_HealthCareOrganizationRevenueSourcesDomain" xlink:to="bioc_BlueCrossBlueShieldMember" order="10730.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_HealthCareOrganizationRevenueSourcesDomain" xlink:to="bioc_UnitedHealthcareMember" order="10750.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ConcentrationRiskLineItems" xlink:to="us-gaap_ConcentrationRiskPercentage1" order="10780.00" priority="2" use="optional"/> |
| | </link:definitionLink> |
| <link:roleRef roleURI="http://www.biocept.com/20210630/taxonomy/role/DisclosureLiquidityAdditionalInformationDetail" xlink:href="bioc-20210630.xsd#Role_DisclosureLiquidityAdditionalInformationDetail" xlink:type="simple"/> |
| <link:definitionLink xlink:type="extended" xlink:role="http://www.biocept.com/20210630/taxonomy/role/DisclosureLiquidityAdditionalInformationDetail"> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCosts" xlink:type="locator" xlink:label="bioc_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCosts"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SharePrice" xlink:type="locator" xlink:label="us-gaap_SharePrice"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromIssuanceOfWarrants" xlink:type="locator" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_OtherNonInterestBearingCurrentLiabilities" xlink:type="locator" xlink:label="bioc_OtherNonInterestBearingCurrentLiabilities"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_AggregateNetInterestBearingIndebtednessDueWithinOneYear" xlink:type="locator" xlink:label="bioc_AggregateNetInterestBearingIndebtednessDueWithinOneYear"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_AggregateNetInterestBearingIndebtedness" xlink:type="locator" xlink:label="bioc_AggregateNetInterestBearingIndebtedness"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetIncomeLoss" xlink:type="locator" xlink:label="us-gaap_NetIncomeLoss"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:type="locator" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_Cash" xlink:type="locator" xlink:label="us-gaap_Cash"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_WarrantMember" xlink:type="locator" xlink:label="us-gaap_WarrantMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain" xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:type="locator" xlink:label="us-gaap_StatementEquityComponentsAxis"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FebruaryTwoThousandAndNineteenAndMarchTwoThousandAndNineteenWarrantRepricingAndExchangeTransactionMember" xlink:type="locator" xlink:label="bioc_FebruaryTwoThousandAndNineteenAndMarchTwoThousandAndNineteenWarrantRepricingAndExchangeTransactionMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightAxis"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ScheduleOfLiquidityAndManagementsPlansTable" xlink:type="locator" xlink:label="bioc_ScheduleOfLiquidityAndManagementsPlansTable"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_LiquidityAndManagementsPlansLineItems" xlink:type="locator" xlink:label="bioc_LiquidityAndManagementsPlansLineItems"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="bioc_ScheduleOfLiquidityAndManagementsPlansTable" order="10010.00" priority="2" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="bioc_ScheduleOfLiquidityAndManagementsPlansTable" xlink:to="us-gaap_ClassOfWarrantOrRightAxis" order="10040.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain" order="10070.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="bioc_FebruaryTwoThousandAndNineteenAndMarchTwoThousandAndNineteenWarrantRepricingAndExchangeTransactionMember" order="10090.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="bioc_ScheduleOfLiquidityAndManagementsPlansTable" xlink:to="us-gaap_StatementEquityComponentsAxis" order="10120.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain" order="10150.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_WarrantMember" order="10170.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="us-gaap_Cash" order="10260.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit" order="10300.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="us-gaap_NetIncomeLoss" order="10340.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities" order="10380.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="bioc_AggregateNetInterestBearingIndebtedness" order="10420.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="bioc_AggregateNetInterestBearingIndebtednessDueWithinOneYear" order="10460.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="bioc_OtherNonInterestBearingCurrentLiabilities" order="10500.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" order="10570.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="us-gaap_ProceedsFromIssuanceOfWarrants" order="10650.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="us-gaap_SharePrice" order="10690.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="bioc_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCosts" order="10800.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LiquidityAndManagementsPlansLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodSharesNewIssues" order="10820.00" priority="2" use="optional"/> |
| | </link:definitionLink> |
| <link:roleRef roleURI="http://www.biocept.com/20210630/taxonomy/role/DisclosureSalesOfEquitySecuritiesAdditionalInformationDetail" xlink:href="bioc-20210630.xsd#Role_DisclosureSalesOfEquitySecuritiesAdditionalInformationDetail" xlink:type="simple"/> |
| <link:definitionLink xlink:type="extended" xlink:role="http://www.biocept.com/20210630/taxonomy/role/DisclosureSalesOfEquitySecuritiesAdditionalInformationDetail"> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_PercentageOfFixedCommissionToSalesAgentRateEqualToGrossSalesPricePerShareOfCommonStockSoldUnderSalesAgreement" xlink:type="locator" xlink:label="bioc_PercentageOfFixedCommissionToSalesAgentRateEqualToGrossSalesPricePerShareOfCommonStockSoldUnderSalesAgreement"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_NumberOfDaysPriorNoticeToTerminateSalesAgreement" xlink:type="locator" xlink:label="bioc_NumberOfDaysPriorNoticeToTerminateSalesAgreement"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCosts" xlink:type="locator" xlink:label="bioc_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCosts"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WarrantInducementExpense" xlink:type="locator" xlink:label="bioc_WarrantInducementExpense"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueAdjustmentOfWarrants" xlink:type="locator" xlink:label="us-gaap_FairValueAdjustmentOfWarrants"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SharePrice" xlink:type="locator" xlink:label="us-gaap_SharePrice"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromWarrantExercises" xlink:type="locator" xlink:label="us-gaap_ProceedsFromWarrantExercises"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromIssuanceOfWarrants" xlink:type="locator" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_CantorFitzgeraldAndCoMember" xlink:type="locator" xlink:label="bioc_CantorFitzgeraldAndCoMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:type="locator" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_CounterpartyNameAxis" xlink:type="locator" xlink:label="srt_CounterpartyNameAxis"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ControlledEquityOfferingSalesAgreementMember" xlink:type="locator" xlink:label="bioc_ControlledEquityOfferingSalesAgreementMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:type="locator" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:type="locator" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_2"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TypeOfArrangementAxis" xlink:type="locator" xlink:label="us-gaap_TypeOfArrangementAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MinimumMember" xlink:type="locator" xlink:label="srt_MinimumMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember" xlink:type="locator" xlink:label="srt_MaximumMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember" xlink:type="locator" xlink:label="srt_RangeMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeAxis" xlink:type="locator" xlink:label="srt_RangeAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_WarrantMember" xlink:type="locator" xlink:label="us-gaap_WarrantMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain" xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:type="locator" xlink:label="us-gaap_StatementEquityComponentsAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OverAllotmentOptionMember" xlink:type="locator" xlink:label="us-gaap_OverAllotmentOptionMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:type="locator" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:type="locator" xlink:label="us-gaap_SubsidiarySaleOfStockAxis"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FebruaryTwoThousandAndNineteenAndMarchTwoThousandAndNineteenWarrantRepricingAndExchangeTransactionMember" xlink:type="locator" xlink:label="bioc_FebruaryTwoThousandAndNineteenAndMarchTwoThousandAndNineteenWarrantRepricingAndExchangeTransactionMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:type="locator" xlink:label="us-gaap_ScheduleOfStockByClassTable"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfStockLineItems" xlink:type="locator" xlink:label="us-gaap_ClassOfStockLineItems"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ScheduleOfStockByClassTable" order="10010.00" priority="2" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfStockByClassTable" xlink:to="us-gaap_ClassOfWarrantOrRightAxis" order="10040.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain" order="10070.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="bioc_FebruaryTwoThousandAndNineteenAndMarchTwoThousandAndNineteenWarrantRepricingAndExchangeTransactionMember" order="10090.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfStockByClassTable" xlink:to="us-gaap_SubsidiarySaleOfStockAxis" order="10140.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_SubsidiarySaleOfStockAxis" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain" order="10170.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SaleOfStockNameOfTransactionDomain" xlink:to="us-gaap_OverAllotmentOptionMember" order="10190.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfStockByClassTable" xlink:to="us-gaap_StatementEquityComponentsAxis" order="10220.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain" order="10250.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_WarrantMember" order="10270.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfStockByClassTable" xlink:to="srt_RangeAxis" order="10360.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember" order="10390.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RangeMember" xlink:to="srt_MaximumMember" order="10410.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RangeMember" xlink:to="srt_MinimumMember" order="10430.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfStockByClassTable" xlink:to="us-gaap_TypeOfArrangementAxis" order="10440.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_TypeOfArrangementAxis" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember_2" order="10450.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_TypeOfArrangementAxis" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember" order="10470.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:to="bioc_ControlledEquityOfferingSalesAgreementMember" order="10490.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfStockByClassTable" xlink:to="srt_CounterpartyNameAxis" order="10600.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_CounterpartyNameAxis" xlink:to="srt_RepurchaseAgreementCounterpartyNameDomain" order="10630.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RepurchaseAgreementCounterpartyNameDomain" xlink:to="bioc_CantorFitzgeraldAndCoMember" order="10650.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ProceedsFromIssuanceOfWarrants" order="10780.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ProceedsFromWarrantExercises" order="10820.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" order="10860.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_SharePrice" order="10940.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_FairValueAdjustmentOfWarrants" order="10980.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="bioc_WarrantInducementExpense" order="11020.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodSharesNewIssues" order="11100.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="bioc_ProceedsFromIssuanceOfCommonStockNetOfIssuanceCosts" order="11170.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="bioc_NumberOfDaysPriorNoticeToTerminateSalesAgreement" order="11420.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="bioc_PercentageOfFixedCommissionToSalesAgentRateEqualToGrossSalesPricePerShareOfCommonStockSoldUnderSalesAgreement" order="11460.00" priority="2" use="optional"/> |
| | </link:definitionLink> |
| <link:roleRef roleURI="http://www.biocept.com/20210630/taxonomy/role/DisclosureFairValueMeasurementAdditionalInformationDetail" xlink:href="bioc-20210630.xsd#Role_DisclosureFairValueMeasurementAdditionalInformationDetail" xlink:type="simple"/> |
| <link:definitionLink xlink:type="extended" xlink:role="http://www.biocept.com/20210630/taxonomy/role/DisclosureFairValueMeasurementAdditionalInformationDetail"> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WarrantInducementExpense" xlink:type="locator" xlink:label="bioc_WarrantInducementExpense"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ClassOfWarrantsOrRightsEligibleForPriceModification" xlink:type="locator" xlink:label="bioc_ClassOfWarrantsOrRightsEligibleForPriceModification"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_EstimatedFairValueOfWarrantsIncreased" xlink:type="locator" xlink:label="bioc_EstimatedFairValueOfWarrantsIncreased"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_EstimatedFairValueOfWarrants" xlink:type="locator" xlink:label="bioc_EstimatedFairValueOfWarrants"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_AdjustedExercisePriceOfWarrants" xlink:type="locator" xlink:label="bioc_AdjustedExercisePriceOfWarrants"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ClassOfWarrantOrRightsTerm" xlink:type="locator" xlink:label="bioc_ClassOfWarrantOrRightsTerm"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_UnregisteredWarrantsIssuedGrantDateFairValue" xlink:type="locator" xlink:label="bioc_UnregisteredWarrantsIssuedGrantDateFairValue"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_IssuanceOfUnregisteredWarrantsToPurchaseCommonStockShares" xlink:type="locator" xlink:label="bioc_IssuanceOfUnregisteredWarrantsToPurchaseCommonStockShares"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_EstimatedGrantDateFairValueOfWarrants" xlink:type="locator" xlink:label="bioc_EstimatedGrantDateFairValueOfWarrants"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1" xlink:type="locator" xlink:label="us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WarrantInducementTransactionMember" xlink:type="locator" xlink:label="bioc_WarrantInducementTransactionMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:type="locator" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:type="locator" xlink:label="us-gaap_SubsidiarySaleOfStockAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MinimumMember" xlink:type="locator" xlink:label="srt_MinimumMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember" xlink:type="locator" xlink:label="srt_MaximumMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember" xlink:type="locator" xlink:label="srt_RangeMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeAxis" xlink:type="locator" xlink:label="srt_RangeAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:type="locator" xlink:label="us-gaap_FairValueInputsLevel3Member"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_2"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:type="locator" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueMeasurementsNonrecurringMember" xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsNonrecurringMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_2"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:type="locator" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:type="locator" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:type="locator" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" order="10010.00" priority="2" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="us-gaap_FairValueByMeasurementFrequencyAxis" order="10040.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:to="us-gaap_FairValueMeasurementFrequencyDomain_2" order="10050.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:to="us-gaap_FairValueMeasurementFrequencyDomain" order="10070.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementFrequencyDomain" xlink:to="us-gaap_FairValueMeasurementsNonrecurringMember" order="10090.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="us-gaap_FairValueByFairValueHierarchyLevelAxis" order="10100.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_2" order="10110.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" order="10130.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel3Member" order="10150.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="srt_RangeAxis" order="10160.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember" order="10190.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RangeMember" xlink:to="srt_MaximumMember" order="10210.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RangeMember" xlink:to="srt_MinimumMember" order="10230.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="us-gaap_SubsidiarySaleOfStockAxis" order="10240.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_SubsidiarySaleOfStockAxis" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain" order="10270.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SaleOfStockNameOfTransactionDomain" xlink:to="bioc_WarrantInducementTransactionMember" order="10290.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1" order="10340.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="bioc_EstimatedGrantDateFairValueOfWarrants" order="10390.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="bioc_IssuanceOfUnregisteredWarrantsToPurchaseCommonStockShares" order="10410.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="bioc_UnregisteredWarrantsIssuedGrantDateFairValue" order="10430.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" order="10450.00" priority="2" use="optional"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="bioc_WarrantInducementExpense" order="10910.00" priority="2" use="optional"/> |
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| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_WarrantsAndRightsOutstandingMeasurementInput" xlink:type="locator" xlink:label="us-gaap_WarrantsAndRightsOutstandingMeasurementInput"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SharePrice" xlink:type="locator" xlink:label="us-gaap_SharePrice"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MeasurementInputPriceVolatilityMember" xlink:type="locator" xlink:label="us-gaap_MeasurementInputPriceVolatilityMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MeasurementInputExpectedTermMember" xlink:type="locator" xlink:label="us-gaap_MeasurementInputExpectedTermMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MeasurementInputDiscountRateMember" xlink:type="locator" xlink:label="us-gaap_MeasurementInputDiscountRateMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MeasurementInputExpectedDividendRateMember" xlink:type="locator" xlink:label="us-gaap_MeasurementInputExpectedDividendRateMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MeasurementInputExercisePriceMember" xlink:type="locator" xlink:label="us-gaap_MeasurementInputExercisePriceMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MeasurementInputTypeDomain" xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeDomain"/> |
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| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MeasurementInputTypeAxis" xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeAxis"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_TenJanuaryTwoThousandTwentyWarrantInducementTransactionMember" xlink:type="locator" xlink:label="bioc_TenJanuaryTwoThousandTwentyWarrantInducementTransactionMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:type="locator" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:type="locator" xlink:label="us-gaap_SubsidiarySaleOfStockAxis"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WarrantFairValueBlackScholesMethodTable" xlink:type="locator" xlink:label="bioc_WarrantFairValueBlackScholesMethodTable"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WarrantFairValueBlackScholesMethodLineItems" xlink:type="locator" xlink:label="bioc_WarrantFairValueBlackScholesMethodLineItems"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_WarrantFairValueBlackScholesMethodLineItems" xlink:to="us-gaap_SharePrice" order="10260.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_WarrantFairValueBlackScholesMethodLineItems" xlink:to="us-gaap_WarrantsAndRightsOutstandingMeasurementInput" order="10300.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_WarrantFairValueBlackScholesMethodLineItems" xlink:to="us-gaap_WarrantsAndRightsOutstandingTerm" order="10420.00" priority="2" use="optional"/> |
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| <link:roleRef roleURI="http://www.biocept.com/20210630/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" xlink:href="bioc-20210630.xsd#Role_DisclosureLeasesAdditionalInformationDetail" xlink:type="simple"/> |
| <link:definitionLink xlink:type="extended" xlink:role="http://www.biocept.com/20210630/taxonomy/role/DisclosureLeasesAdditionalInformationDetail"> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability" xlink:type="locator" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:type="locator" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent" xlink:type="locator" xlink:label="us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" xlink:type="locator" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FinanceLeaseWeightedAverageRemainingLeaseTerm1" xlink:type="locator" xlink:label="us-gaap_FinanceLeaseWeightedAverageRemainingLeaseTerm1"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ReimbursableLeaseholdImprovementCosts" xlink:type="locator" xlink:label="bioc_ReimbursableLeaseholdImprovementCosts"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_LesseeOperatingLeaseInitialMonthlyLeasePayments" xlink:type="locator" xlink:label="bioc_LesseeOperatingLeaseInitialMonthlyLeasePayments"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLeasesRentExpenseNet" xlink:type="locator" xlink:label="us-gaap_OperatingLeasesRentExpenseNet"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_AdditionalRentPaymentOfPercentage" xlink:type="locator" xlink:label="bioc_AdditionalRentPaymentOfPercentage"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_AdditionalLeaseholdImprovementAllowance" xlink:type="locator" xlink:label="bioc_AdditionalLeaseholdImprovementAllowance"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_LeaseholdImprovementAllowance" xlink:type="locator" xlink:label="bioc_LeaseholdImprovementAllowance"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LeaseAndRentalExpense" xlink:type="locator" xlink:label="us-gaap_LeaseAndRentalExpense"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LesseeOperatingLeaseDescription" xlink:type="locator" xlink:label="us-gaap_LesseeOperatingLeaseDescription"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LesseeOperatingLeaseTermOfContract" xlink:type="locator" xlink:label="us-gaap_LesseeOperatingLeaseTermOfContract"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_OperatingLeaseCommencementDate" xlink:type="locator" xlink:label="bioc_OperatingLeaseCommencementDate"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AreaOfLand" xlink:type="locator" xlink:label="us-gaap_AreaOfLand"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_AdditionalExtensionFacilityExtendingLease" xlink:type="locator" xlink:label="bioc_AdditionalExtensionFacilityExtendingLease"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LesseeOperatingLeaseExistenceOfOptionToExtend" xlink:type="locator" xlink:label="us-gaap_LesseeOperatingLeaseExistenceOfOptionToExtend"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LeaseExpirationDate1" xlink:type="locator" xlink:label="us-gaap_LeaseExpirationDate1"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LesseeOperatingLeaseOptionToExtend" xlink:type="locator" xlink:label="us-gaap_LesseeOperatingLeaseOptionToExtend"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LesseeOperatingLeaseDiscountRate" xlink:type="locator" xlink:label="us-gaap_LesseeOperatingLeaseDiscountRate"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLeaseLiability" xlink:type="locator" xlink:label="us-gaap_OperatingLeaseLiability"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:type="locator" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_OperatingLeaseTerm" xlink:type="locator" xlink:label="bioc_OperatingLeaseTerm"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLeasePayments" xlink:type="locator" xlink:label="us-gaap_OperatingLeasePayments"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_OperatingLeaseTransactionFrequencyOfPeriodicPayment" xlink:type="locator" xlink:label="bioc_OperatingLeaseTransactionFrequencyOfPeriodicPayment"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FinanceLeaseTransactionCommitmentObligationMonthAndYear" xlink:type="locator" xlink:label="bioc_FinanceLeaseTransactionCommitmentObligationMonthAndYear"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FinanceLeaseTransactionAmountDueUnderFinancingArrangement" xlink:type="locator" xlink:label="bioc_FinanceLeaseTransactionAmountDueUnderFinancingArrangement"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FinanceLeaseTransactionMonthlyRentalPayments" xlink:type="locator" xlink:label="bioc_FinanceLeaseTransactionMonthlyRentalPayments"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FinanceLeaseTransactionNumberOfInstallmentPayments" xlink:type="locator" xlink:label="bioc_FinanceLeaseTransactionNumberOfInstallmentPayments"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FinanceLeaseTransactionFrequencyOfPeriodicPayment" xlink:type="locator" xlink:label="bioc_FinanceLeaseTransactionFrequencyOfPeriodicPayment"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ProceedsFromLenderToFundFinanceLeaseObligation" xlink:type="locator" xlink:label="bioc_ProceedsFromLenderToFundFinanceLeaseObligation"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FinanceLeaseDepreciationExpense" xlink:type="locator" xlink:label="bioc_FinanceLeaseDepreciationExpense"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FinanceLeaseLesseeAccumulatedDeprecation" xlink:type="locator" xlink:label="bioc_FinanceLeaseLesseeAccumulatedDeprecation"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FinanceLeasedAssetsGross" xlink:type="locator" xlink:label="bioc_FinanceLeasedAssetsGross"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LesseeFinanceLeaseTermOfContract1" xlink:type="locator" xlink:label="us-gaap_LesseeFinanceLeaseTermOfContract1"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FinanceLeaseRightOfUseAsset" xlink:type="locator" xlink:label="us-gaap_FinanceLeaseRightOfUseAsset"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_MesaRimRoadInSanDiegoCaliforniaMember" xlink:type="locator" xlink:label="bioc_MesaRimRoadInSanDiegoCaliforniaMember"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_NancyRidgeRoadInSanDiegoCaliforniaMember" xlink:type="locator" xlink:label="bioc_NancyRidgeRoadInSanDiegoCaliforniaMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_SegmentGeographicalDomain" xlink:type="locator" xlink:label="srt_SegmentGeographicalDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_StatementGeographicalAxis" xlink:type="locator" xlink:label="srt_StatementGeographicalAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AccountingStandardsUpdate201602Member" xlink:type="locator" xlink:label="us-gaap_AccountingStandardsUpdate201602Member"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:type="locator" xlink:label="us-gaap_TypeOfAdoptionMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:type="locator" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember" xlink:type="locator" xlink:label="srt_MaximumMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MinimumMember" xlink:type="locator" xlink:label="srt_MinimumMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember" xlink:type="locator" xlink:label="srt_RangeMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeAxis" xlink:type="locator" xlink:label="srt_RangeAxis"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_LeasesTable" xlink:type="locator" xlink:label="bioc_LeasesTable"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_LeasesLineItems" xlink:type="locator" xlink:label="bioc_LeasesLineItems"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="bioc_LeasesLineItems" xlink:to="bioc_LeasesTable" order="10010.00" priority="2" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="bioc_LeasesTable" xlink:to="srt_RangeAxis" order="10040.00" priority="2" use="optional"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LeasesLineItems" xlink:to="us-gaap_LesseeOperatingLeaseDiscountRate" order="13200.00" priority="2" use="optional"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LeasesLineItems" xlink:to="us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent" order="13970.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LeasesLineItems" xlink:to="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" order="14010.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="bioc_LeasesLineItems" xlink:to="us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability" order="14050.00" priority="2" use="optional"/> |
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| <link:definitionLink xlink:type="extended" xlink:role="http://www.biocept.com/20210630/taxonomy/role/DisclosureStockBasedCompensationAdditionalInformationDetail"> |
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| | <link:loc xlink:href="bioc-20210630.xsd#bioc_StockOptionsAndRestrictedStockUnitsMember" xlink:type="locator" xlink:label="bioc_StockOptionsAndRestrictedStockUnitsMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:type="locator" xlink:label="us-gaap_RestrictedStockUnitsRSUMember"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" order="11490.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" order="11540.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" order="11620.00" priority="2" use="optional"/> |
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| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsDiscountRateBondEquivalentYield" xlink:type="locator" xlink:label="bioc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsDiscountRateBondEquivalentYield"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate"/> |
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| | <link:loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember" xlink:type="locator" xlink:label="srt_MaximumMember"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" order="10320.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum" order="10360.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum" order="10380.00" priority="2" use="optional"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue" order="10750.00" priority="2" use="optional"/> |
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| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SellingAndMarketingExpenseMember" xlink:type="locator" xlink:label="us-gaap_SellingAndMarketingExpenseMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_GeneralAndAdministrativeExpenseMember" xlink:type="locator" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:type="locator" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CostOfSalesMember" xlink:type="locator" xlink:label="us-gaap_CostOfSalesMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:type="locator" xlink:label="us-gaap_IncomeStatementLocationDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:type="locator" xlink:label="us-gaap_IncomeStatementLocationAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:type="locator" xlink:label="us-gaap_EmployeeStockOptionMember"/> |
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| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:type="locator" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_IncomeStatementLocationAxis" xlink:to="us-gaap_IncomeStatementLocationDomain" order="10210.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_CostOfSalesMember" order="10230.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_ResearchAndDevelopmentExpenseMember" order="10250.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_GeneralAndAdministrativeExpenseMember" order="10270.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_SellingAndMarketingExpenseMember" order="10290.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_AllocatedShareBasedCompensationExpense" order="10320.00" priority="2" use="optional"/> |
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| <link:roleRef roleURI="http://www.biocept.com/20210630/taxonomy/role/DisclosureCommonStockWarrantsOutstandingSummaryOfEquityClassifiedCommonStockWarrantActivityDetail" xlink:href="bioc-20210630.xsd#Role_DisclosureCommonStockWarrantsOutstandingSummaryOfEquityClassifiedCommonStockWarrantActivityDetail" xlink:type="simple"/> |
| <link:definitionLink xlink:type="extended" xlink:role="http://www.biocept.com/20210630/taxonomy/role/DisclosureCommonStockWarrantsOutstandingSummaryOfEquityClassifiedCommonStockWarrantActivityDetail"> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ClassOfWarrantsOrRightsWeightedAverageRemainingContractualLife" xlink:type="locator" xlink:label="bioc_ClassOfWarrantsOrRightsWeightedAverageRemainingContractualLife"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsExpired" xlink:type="locator" xlink:label="bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsExpired"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsExercised" xlink:type="locator" xlink:label="bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsExercised"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsIssued" xlink:type="locator" xlink:label="bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsIssued"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsOutstanding" xlink:type="locator" xlink:label="bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsOutstanding"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ClassOfWarrantsOrRightsExpiredDuringPeriod" xlink:type="locator" xlink:label="bioc_ClassOfWarrantsOrRightsExpiredDuringPeriod"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_StockIssuedDuringPeriodForClassWarrantsOrRightsExercised" xlink:type="locator" xlink:label="bioc_StockIssuedDuringPeriodForClassWarrantsOrRightsExercised"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ClassOfWarrantsOrRightsIssuedDuringPeriod" xlink:type="locator" xlink:label="bioc_ClassOfWarrantsOrRightsIssuedDuringPeriod"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_WarrantMember" xlink:type="locator" xlink:label="us-gaap_WarrantMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain" xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:type="locator" xlink:label="us-gaap_StatementEquityComponentsAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightTable" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightTable"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightLineItems" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightTable" order="10010.00" priority="2" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ClassOfWarrantOrRightTable" xlink:to="us-gaap_StatementEquityComponentsAxis" order="10040.00" priority="2" use="optional"/> |
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| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_WarrantMember" order="10090.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightOutstanding" order="10240.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="bioc_ClassOfWarrantsOrRightsIssuedDuringPeriod" order="10320.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="bioc_StockIssuedDuringPeriodForClassWarrantsOrRightsExercised" order="10400.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="bioc_ClassOfWarrantsOrRightsExpiredDuringPeriod" order="10480.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsOutstanding" order="10670.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsIssued" order="10750.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsExercised" order="10830.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="bioc_WeightedAveragePricePerShareClassOfWarrantsOrRightsExpired" order="10910.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="bioc_ClassOfWarrantsOrRightsWeightedAverageRemainingContractualLife" order="11100.00" priority="2" use="optional"/> |
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| <link:definitionLink xlink:type="extended" xlink:role="http://www.biocept.com/20210630/taxonomy/role/DisclosureCommonStockWarrantsOutstandingAdditionalInformationDetail"> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_CommonStockWarrantsOutstandingIntrinsicValue" xlink:type="locator" xlink:label="bioc_CommonStockWarrantsOutstandingIntrinsicValue"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_ClassOfWarrantsOrRightsExpirationDate" xlink:type="locator" xlink:label="bioc_ClassOfWarrantsOrRightsExpirationDate"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_JanuaryTwoThousandTwentyWarrantExerciseInducementOfferingMember" xlink:type="locator" xlink:label="bioc_JanuaryTwoThousandTwentyWarrantExerciseInducementOfferingMember"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_DecemberTwoThousandNineteenUnderwrittenOfferingMember" xlink:type="locator" xlink:label="bioc_DecemberTwoThousandNineteenUnderwrittenOfferingMember"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_MayTwoThousandNineteenWarrantExerciseInducementOfferingMember" xlink:type="locator" xlink:label="bioc_MayTwoThousandNineteenWarrantExerciseInducementOfferingMember"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_MarchTwoThousandNineteenFinancingTransactionMember" xlink:type="locator" xlink:label="bioc_MarchTwoThousandNineteenFinancingTransactionMember"/> |
| | <link:loc xlink:href="bioc-20210630.xsd#bioc_FebruaryTwoThousandNineteenFinancingTransactionMember" xlink:type="locator" xlink:label="bioc_FebruaryTwoThousandNineteenFinancingTransactionMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:type="locator" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:type="locator" xlink:label="us-gaap_SubsidiarySaleOfStockAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_WarrantMember" xlink:type="locator" xlink:label="us-gaap_WarrantMember"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain" xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:type="locator" xlink:label="us-gaap_StatementEquityComponentsAxis"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightTable" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightTable"/> |
| | <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightLineItems" xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightTable" order="10010.00" priority="2" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ClassOfWarrantOrRightTable" xlink:to="us-gaap_StatementEquityComponentsAxis" order="10040.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain" order="10070.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_WarrantMember" order="10090.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ClassOfWarrantOrRightTable" xlink:to="us-gaap_SubsidiarySaleOfStockAxis" order="10180.00" priority="2" use="optional"/> |
| | <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_SubsidiarySaleOfStockAxis" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain" order="10210.00" priority="2" use="optional"/> |
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