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    <ReturnTs>2026-03-25T21:51:11Z</ReturnTs>
    <TaxPeriodEndDt>2025-12-31</TaxPeriodEndDt>
    <ReturnTypeCd>990EZ</ReturnTypeCd>
    <TaxPeriodBeginDt>2025-01-01</TaxPeriodBeginDt>
    <Filer>
      <EIN>921158130</EIN>
      <BusinessName>
        <BusinessNameLine1Txt>MECHANICAL INDUSTRY LABOR FUND</BusinessNameLine1Txt>
      </BusinessName>
      <BusinessNameControlTxt>MECH</BusinessNameControlTxt>
      <PhoneNum>2604905693</PhoneNum>
      <USAddress>
        <AddressLine1Txt>2930 W Ludwig Road</AddressLine1Txt>
        <CityNm>Fort Wayne</CityNm>
        <StateAbbreviationCd>IN</StateAbbreviationCd>
        <ZIPCd>46818</ZIPCd>
      </USAddress>
    </Filer>
    <BusinessOfficerGrp>
      <PersonNm>Kent L Prosser</PersonNm>
      <PersonTitleTxt>Chairman/ Labor Trustee</PersonTitleTxt>
      <PhoneNum>2604905693</PhoneNum>
      <SignatureDt>2026-03-25</SignatureDt>
    </BusinessOfficerGrp>
    <TaxYr>2025</TaxYr>
    <BuildTS>2025-03-06 01:10:19Z</BuildTS>
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      <MethodOfAccountingCashInd>X</MethodOfAccountingCashInd>
      <ScheduleBNotRequiredInd>X</ScheduleBNotRequiredInd>
      <Organization501cInd organization501cTypeTxt="6">X</Organization501cInd>
      <TypeOfOrganizationTrustInd>X</TypeOfOrganizationTrustInd>
      <GrossReceiptsAmt>84033</GrossReceiptsAmt>
      <InfoInScheduleOPartIInd>X</InfoInScheduleOPartIInd>
      <ContributionsGiftsGrantsEtcAmt>84033</ContributionsGiftsGrantsEtcAmt>
      <TotalRevenueAmt>84033</TotalRevenueAmt>
      <FeesAndOtherPymtToIndCntrctAmt>0</FeesAndOtherPymtToIndCntrctAmt>
      <OtherExpensesTotalAmt>959</OtherExpensesTotalAmt>
      <TotalExpensesAmt>959</TotalExpensesAmt>
      <ExcessOrDeficitForYearAmt>83074</ExcessOrDeficitForYearAmt>
      <NetAssetsOrFundBalancesBOYAmt>138452</NetAssetsOrFundBalancesBOYAmt>
      <NetAssetsOrFundBalancesEOYAmt>221526</NetAssetsOrFundBalancesEOYAmt>
      <CashSavingsAndInvestmentsGrp>
        <BOYAmt>138452</BOYAmt>
        <EOYAmt>221526</EOYAmt>
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      <Form990TotalAssetsGrp>
        <BOYAmt>138452</BOYAmt>
        <EOYAmt>221526</EOYAmt>
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        <BOYAmt>138452</BOYAmt>
        <EOYAmt>221526</EOYAmt>
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      <PrimaryExemptPurposeTxt>a. Improving communication between representatives of labor and management b. Providing employees and Employers with opportunities to study and explore new and innovative joint approaches to achieving organizational effectiveness c. Assisting Employees and Employers in solving problems of mutual concern not susceptible to resolution within the collective bargaining process d. Studying, exploring, and implementing ways of eliminating potential problems which reduce the competitiveness and inhibit the economic development of the Pipe Trades Industry. e. Sponsoring programs which improve job security, enhance economic and community development, and promote the general welfare of the community. f.Expanding and improving working relationships between Employees and Employers. g. Encouraging free collective bargaining by establishing continuing mechanisms for communication between Employees and their Employers through the formation and operation of a labor management committee.</PrimaryExemptPurposeTxt>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>Negotiation of Collective Bargaining and subsequent labor advancement meetings.</DescriptionProgramSrvcAccomTxt>
      </ProgramSrvcAccomplishmentGrp>
      <TotalProgramServiceExpensesAmt>0</TotalProgramServiceExpensesAmt>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Kent Prosser</PersonNm>
        <TitleTxt>Chair</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Bill Meyer</PersonNm>
        <TitleTxt>Management Trustee</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Curt Mirwaldt</PersonNm>
        <TitleTxt>Secretary</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Christopher Brown</PersonNm>
        <TitleTxt>Labor Trustee</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Juan Arambula</PersonNm>
        <TitleTxt>Management Trustee</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Jess Wagner</PersonNm>
        <TitleTxt>Labor Trustee</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Lester Zimmerman</PersonNm>
        <TitleTxt>Labor Trustee</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Kurt Prosser</PersonNm>
        <TitleTxt>Labor Trustee</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <ActivitiesNotPreviouslyRptInd>false</ActivitiesNotPreviouslyRptInd>
      <ChgMadeToOrgnzngDocNotRptInd>false</ChgMadeToOrgnzngDocNotRptInd>
      <OrganizationHadUBIInd>false</OrganizationHadUBIInd>
      <SubjectToProxyTaxInd referenceDocumentName="IRS990ScheduleC">false</SubjectToProxyTaxInd>
      <OrganizationDissolvedEtcInd referenceDocumentName="IRS990ScheduleN BinaryAttachment">false</OrganizationDissolvedEtcInd>
      <DirectIndirectPltclExpendAmt>0</DirectIndirectPltclExpendAmt>
      <Form1120PolFiledInd>false</Form1120PolFiledInd>
      <MadeLoansToFromOfficersInd>false</MadeLoansToFromOfficersInd>
      <StatesWhereCopyOfReturnIsFldCd>IN</StatesWhereCopyOfReturnIsFldCd>
      <BooksInCareOfDetail>
        <BusinessName>
          <BusinessNameLine1Txt>Plumbers and Steamfitters Local 166</BusinessNameLine1Txt>
        </BusinessName>
        <USAddress>
          <AddressLine1Txt>2930 West Ludwig Road</AddressLine1Txt>
          <CityNm>Fort Wayne</CityNm>
          <StateAbbreviationCd>IN</StateAbbreviationCd>
          <ZIPCd>46818</ZIPCd>
        </USAddress>
        <PhoneNum>2604905696</PhoneNum>
      </BooksInCareOfDetail>
      <ForeignFinancialAccountInd>false</ForeignFinancialAccountInd>
      <ForeignOfficeInd>false</ForeignOfficeInd>
      <DonorAdvisedFndsInd>false</DonorAdvisedFndsInd>
      <OperateHospitalInd>false</OperateHospitalInd>
      <TanningServicesProvidedInd>false</TanningServicesProvidedInd>
      <RelatedOrganizationCtrlEntInd>false</RelatedOrganizationCtrlEntInd>
      <TransactionWithControlEntInd>false</TransactionWithControlEntInd>
      <PoliticalCampaignActyInd referenceDocumentName="IRS990ScheduleC">false</PoliticalCampaignActyInd>
      <LobbyingActivitiesInd referenceDocumentName="IRS990ScheduleC">false</LobbyingActivitiesInd>
      <SchoolOperatingInd referenceDocumentName="IRS990ScheduleE">false</SchoolOperatingInd>
      <TrnsfrExmptNonChrtblRltdOrgInd>false</TrnsfrExmptNonChrtblRltdOrgInd>
      <RelatedOrgSect527OrgInd>false</RelatedOrgSect527OrgInd>
      <PartVIOfCompOfHghstPdEmplTxt>NONE</PartVIOfCompOfHghstPdEmplTxt>
      <OtherEmployeePaidOver100kCnt>0</OtherEmployeePaidOver100kCnt>
      <PartVIHghstPdCntrctProfSrvcTxt>NONE</PartVIHghstPdCntrctProfSrvcTxt>
      <CntrctRcvdGreaterThan100KCnt>0</CntrctRcvdGreaterThan100KCnt>
      <FiledScheduleAInd>false</FiledScheduleAInd>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, Line 16</FormAndLineReferenceDesc>
        <ExplanationTxt>Board Meeting Expense (Meeting Space, Food, and Beverage): $868.64 Tax/Accounting (990-EZ Filing): $90</ExplanationTxt>
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