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  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Abstract_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Abstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Reconciliation of Financial Statement to Form 5500 [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Abstract" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Abstract"/>
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    <link:label id="lab_dei_EntityTaxIdentificationNumber_label_en-US" xlink:label="lab_dei_EntityTaxIdentificationNumber" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Tax Identification Number</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityTaxIdentificationNumber"/>
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    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantContribution_019f15a7-0772-779f-aa5a-404d1691ae27_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantContribution" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contributions receivable, participants</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantContribution_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantContribution" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Contributions, Participants</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantContribution" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantContribution"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantContribution" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantContribution" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_LegalEntityAxis_019f15a5-0ff0-7c6d-9bf5-54011bb68388_terseLabel_en-US" xlink:label="lab_dei_LegalEntityAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Legal Entity [Axis]</link:label>
    <link:label id="lab_dei_LegalEntityAxis_label_en-US" xlink:label="lab_dei_LegalEntityAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Legal Entity [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_LegalEntityAxis" xlink:to="lab_dei_LegalEntityAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable_019f15b4-d080-7a5c-8848-3f84c6a8fff3_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">EBP, Description of Plan [Table]</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Description of Plan [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_CoverAbstract_label_en-US" xlink:label="lab_dei_CoverAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cover [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CoverAbstract" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CoverAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CoverAbstract" xlink:to="lab_dei_CoverAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContributionCash_019f15b4-d080-7331-97bd-163fdb241fc2_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContributionCash" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Employer contributions</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContributionCash_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContributionCash" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change in Net Asset Available for Benefit, Increase from Employer Contribution, Cash</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContributionCash" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContributionCash"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContributionCash" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContributionCash" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherIncome_019f15a8-1d8e-7ea5-892b-bed2a453edbc_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherIncome" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other income</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherIncome_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherIncome" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Other Income</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherIncome"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherIncome" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherIncome" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityRegistrantName_019f15a6-9520-74f0-ac76-86e40c781171_terseLabel_en-US" xlink:label="lab_dei_EntityRegistrantName" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Registrant Name</link:label>
    <link:label id="lab_dei_EntityRegistrantName_label_en-US" xlink:label="lab_dei_EntityRegistrantName" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Registrant Name</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityRegistrantName"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityRegistrantName" xlink:to="lab_dei_EntityRegistrantName" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetIncomeLoss_019f15b3-11ac-747a-ae40-3fbc3ce8721d_totalLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net income (loss)</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetIncomeLoss_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Net Income (Loss)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetIncomeLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetIncomeLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetIncomeLoss" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetIncomeLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherContribution_019f15a7-9b39-773c-a325-16eb3bd348f8_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherContribution" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contributions receivable, others</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherContribution_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherContribution" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Contributions, Other</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherContribution" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherContribution"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherContribution" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionOtherContribution" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease_019f15b4-d080-716e-9674-84e479353d9c_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expenses</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change in Net Asset Available for Benefit, Decrease</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease_019f15b4-d080-782a-9884-0fd0d306ba40_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Change in net asset available for benefit</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change in Net Asset Available for Benefit, Increase (Decrease)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease" xlink:type="arc" order="1"/>
    <link:label id="lab_wtm_EBPForm5500Caption_019f15ad-24e5-7c60-89f5-3125a9d8bcc6_terseLabel_en-US" xlink:label="lab_wtm_EBPForm5500Caption" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fidelity bond</link:label>
    <link:label id="lab_wtm_EBPForm5500Caption_label_en-US" xlink:label="lab_wtm_EBPForm5500Caption" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption,</link:label>
    <link:label id="lab_wtm_EBPForm5500Caption_documentation_en-US" xlink:label="lab_wtm_EBPForm5500Caption" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption,</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_wtm_EBPForm5500Caption" xlink:href="wtm-20260630.xsd#wtm_EBPForm5500Caption"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wtm_EBPForm5500Caption" xlink:to="lab_wtm_EBPForm5500Caption" xlink:type="arc" order="1"/>
    <link:label id="lab_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses_019f15b4-d080-75b9-9044-85c43a5fbe9e_terseLabel_en-US" xlink:label="lab_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other expenses</link:label>
    <link:label id="lab_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses_label_en-US" xlink:label="lab_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change In Net Asset Available For Benefit, Decrease From Other Expenses</link:label>
    <link:label id="lab_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses_documentation_en-US" xlink:label="lab_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">EBP, Change In Net Asset Available For Benefit, Decrease From Other Expenses</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses" xlink:href="wtm-20260630.xsd#wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses" xlink:to="lab_wtm_EBPChangeInNetAssetAvailableForBenefitDecreaseFromOtherExpenses" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionEmployerContribution_019f15a5-74cc-7ecb-9beb-dea2a1483367_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionEmployerContribution" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contributions receivable, employers</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionEmployerContribution_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionEmployerContribution" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Contributions, Employers</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionEmployerContribution" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionEmployerContribution"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionEmployerContribution" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionEmployerContribution" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant_019f15b4-d080-7380-aef5-4f4892d3da87_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Benefits paid to participants and beneficiaries</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change in Net Asset Available for Benefit, Decrease from Payment to Participant</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems_019f15b4-d080-7278-80ce-ef87cedb07e7_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">EBP, Description of Plan [Line Items]</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Description of Plan [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanPlanNumber_019f15ad-84dd-71aa-bfb6-2eb4f0e29799_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanPlanNumber" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Plan number</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanPlanNumber_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanPlanNumber" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Plan Number</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanPlanNumber" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanPlanNumber"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanPlanNumber" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanPlanNumber" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock_019f15b8-60f3-7ab1-b6d0-ed9533757f02_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basic Financial Information</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Description of Plan [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants_019f15b4-d080-7d05-a0a0-a33cb623cc04_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of participants</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Number of Participants</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanNumberOfParticipants" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentInformationTable_019f15a3-899e-789f-a4ce-6c438262de2d_terseLabel_en-US" xlink:label="lab_dei_DocumentInformationTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Information [Table]</link:label>
    <link:label id="lab_dei_DocumentInformationTable_label_en-US" xlink:label="lab_dei_DocumentInformationTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Information [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentInformationTable" xlink:to="lab_dei_DocumentInformationTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalAdministrativeExpense_019f15aa-f82d-7ffa-bf83-a6f009e6ccd3_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalAdministrativeExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Administrative service providers (salaries, fees, and commissions)</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalAdministrativeExpense_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalAdministrativeExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Total Administrative Expenses</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalAdministrativeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalAdministrativeExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalAdministrativeExpense" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalAdministrativeExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock_019f15b9-749a-7187-af26-bfb11a22d639_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule I (Form 5500)</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Reconciliation of Financial Statement to Form 5500 [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalIncome_019f15b2-9109-7198-9516-406f5e6d64fc_totalLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalIncome" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total income</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalIncome_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalIncome" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Total Income</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalIncome"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalIncome" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalIncome" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment_019f15b4-d080-77d9-ab80-223856603a73_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Earnings from investments</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment" xlink:type="arc" order="1"/>
    <link:label id="lab_wtm_EBPForm5500CaptionEmployerSecurities_019f15ac-b58d-7926-89e2-525ce17d26d7_terseLabel_en-US" xlink:label="lab_wtm_EBPForm5500CaptionEmployerSecurities" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Employer securities</link:label>
    <link:label id="lab_wtm_EBPForm5500CaptionEmployerSecurities_label_en-US" xlink:label="lab_wtm_EBPForm5500CaptionEmployerSecurities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Employer Securities</link:label>
    <link:label id="lab_wtm_EBPForm5500CaptionEmployerSecurities_documentation_en-US" xlink:label="lab_wtm_EBPForm5500CaptionEmployerSecurities" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Employer Securities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_wtm_EBPForm5500CaptionEmployerSecurities" xlink:href="wtm-20260630.xsd#wtm_EBPForm5500CaptionEmployerSecurities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wtm_EBPForm5500CaptionEmployerSecurities" xlink:to="lab_wtm_EBPForm5500CaptionEmployerSecurities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionAsset_019f15a9-23bc-7d18-bc1c-88ae5832cfc0_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionAsset" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total plan assets</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionAsset_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionAsset" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Total Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionAsset" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionAsset"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionAsset" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionAsset" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease_019f15b4-d080-7d9c-942f-0c32ee01c4de_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change in Net Asset Available for Benefit, Increase</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalExpense_019f15b2-af82-7e8b-bfc0-274e6f89a465_totalLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalExpense" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total expenses</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalExpense_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Total Expenses</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalExpense" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionTotalExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Table_019f15a5-74cc-785b-bae1-3e0037930ac5_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Table" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">EBP, Reconciliation of Financial Statement to Form 5500 [Table]</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Table_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Table" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Reconciliation of Financial Statement to Form 5500 [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Table" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Table"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Table" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500Table" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_AmendmentFlag_019f15a3-a863-75f8-8951-e977efdc969a_terseLabel_en-US" xlink:label="lab_dei_AmendmentFlag" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amendment Flag</link:label>
    <link:label id="lab_dei_AmendmentFlag_label_en-US" xlink:label="lab_dei_AmendmentFlag" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amendment Flag</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_AmendmentFlag"/>
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    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution_019f15b4-d080-71d6-a4f3-20064acdb87c_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Employee contributions</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContribution" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems_019f15a5-74cc-7d9c-83c4-829179aeb59b_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">EBP, Reconciliation of Financial Statement to Form 5500 [Line Items]</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Reconciliation of Financial Statement to Form 5500 [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit_019f15a9-90e1-76bb-8317-95b1ccb8cf63_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net plan assets</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit_019f15b2-7607-760f-9529-c7a893e8c13d_totalLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net plan assets</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Net Asset Available for Benefit</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense_019f15b4-d080-73ae-967e-676d57fce1d3_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Administrative expenses</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Change in Net Asset Available for Benefit, Decrease from Administrative Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_wtm_EBP001Member_019f15a5-1c39-760a-a201-76c8ed39e7a0_terseLabel_en-US" xlink:label="lab_wtm_EBP001Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">EBP 001</link:label>
    <link:label id="lab_wtm_EBP001Member_label_en-US" xlink:label="lab_wtm_EBP001Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP 001 [Member]</link:label>
    <link:label id="lab_wtm_EBP001Member_documentation_en-US" xlink:label="lab_wtm_EBP001Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">EBP 001</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_wtm_EBP001Member" xlink:href="wtm-20260630.xsd#wtm_EBP001Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_wtm_EBP001Member" xlink:to="lab_wtm_EBP001Member" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityDomain_019f15a5-0ff0-774d-b069-1881fd654cab_terseLabel_en-US" xlink:label="lab_dei_EntityDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity [Domain]</link:label>
    <link:label id="lab_dei_EntityDomain_label_en-US" xlink:label="lab_dei_EntityDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityDomain" xlink:to="lab_dei_EntityDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantLoan_019f15ac-382d-7f9c-a361-2e0581c75441_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantLoan" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Participant loans</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantLoan_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantLoan" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Participant Loans</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantLoan" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantLoan"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantLoan" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionParticipantLoan" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant_019f15aa-7243-7349-87c6-da719954c3b4_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Benefits paid (including direct rollovers)</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Benefit Payment and Payments to Provide Benefits</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TextBlock_019f15b5-185f-7bbe-bcdc-498bb466e875_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule I (Form 5500)</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TextBlock_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Reconciliation of Financial Statement to Form 5500 [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TextBlock" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanAbstract_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Description of Plan and Accounting Change [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanAbstract" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentInformationLineItems_019f15a3-899e-7e64-b07f-46bf65f9c7cc_terseLabel_en-US" xlink:label="lab_dei_DocumentInformationLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Information [Line Items]</link:label>
    <link:label id="lab_dei_DocumentInformationLineItems_label_en-US" xlink:label="lab_dei_DocumentInformationLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Information [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentInformationLineItems" xlink:to="lab_dei_DocumentInformationLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentType_019f15a5-e137-75d4-be0e-27953ebaee13_terseLabel_en-US" xlink:label="lab_dei_DocumentType" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Type</link:label>
    <link:label id="lab_dei_DocumentType_label_en-US" xlink:label="lab_dei_DocumentType" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Type</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentType"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentType" xlink:to="lab_dei_DocumentType" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionLiability_019f15a9-6396-774d-bd6c-b00581bebb8e_terseLabel_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionLiability" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total plan liabilities</link:label>
    <link:label id="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionLiability_label_en-US" xlink:label="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionLiability" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">EBP, Form 5500 Caption, Total Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionLiability" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionLiability"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionLiability" xlink:to="lab_us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionLiability" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityCentralIndexKey_019f15a3-899e-704c-9d85-bf7ad79f7437_terseLabel_en-US" xlink:label="lab_dei_EntityCentralIndexKey" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Central Index Key</link:label>
    <link:label id="lab_dei_EntityCentralIndexKey_label_en-US" xlink:label="lab_dei_EntityCentralIndexKey" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Central Index Key</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCentralIndexKey"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCentralIndexKey" xlink:to="lab_dei_EntityCentralIndexKey" xlink:type="arc" order="1"/>
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