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        <FormAndLineReferenceDesc>Part I, line 3:</FormAndLineReferenceDesc>
        <ExplanationTxt>THE MODIFIED CASH METHOD WAS USED IN ACCOUNTING FOR EXPENDITURES IN PART I.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleF>
    <IRS990ScheduleJ documentId="RetDoc1042400001">
      <SeverancePaymentInd>0</SeverancePaymentInd>
      <SupplementalNonqualRtrPlanInd>0</SupplementalNonqualRtrPlanInd>
      <EquityBasedCompArrngmInd>0</EquityBasedCompArrngmInd>
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      <RltdOrgOfficerTrstKeyEmplGrp>
        <PersonNm>Alim Patten</PersonNm>
        <TitleTxt>Business Manager</TitleTxt>
        <BaseCompensationFilingOrgAmt>94122</BaseCompensationFilingOrgAmt>
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        <BonusFilingOrganizationAmount>0</BonusFilingOrganizationAmount>
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        <NontaxableBenefitsFilingOrgAmt>25706</NontaxableBenefitsFilingOrgAmt>
        <NontaxableBenefitsRltdOrgsAmt>0</NontaxableBenefitsRltdOrgsAmt>
        <TotalCompensationFilingOrgAmt>119828</TotalCompensationFilingOrgAmt>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Schedule J, Part I, #3 and Part II:</FormAndLineReferenceDesc>
        <ExplanationTxt>Alim Patten receives compensation and benefits for her work with Astrophysical Research Consortium (ARC) from the University of Washington (UW), an unrelated exempt organization. ARC reimburses UW for her compensation and benefits. Alim Patten also participates in the University of Washington's defined-benefit pension plan. The organization has made reasonable efforts to obtain the annual value of this pension plan, but the value is not available.</ExplanationTxt>
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    <IRS990ScheduleO documentId="RetDoc1044400001">
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part I, Line 6, Volunteers:</FormAndLineReferenceDesc>
        <ExplanationTxt>The volunteers are the board members.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 6</FormAndLineReferenceDesc>
        <ExplanationTxt>ARC is a consortium consisting of nine member universities in 2023.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 7a</FormAndLineReferenceDesc>
        <ExplanationTxt>Each member of ARC has two representatives on the Board of Governors, who are appointed by the member institution's academic administration.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 7b</FormAndLineReferenceDesc>
        <ExplanationTxt>Members have approval rights in accordance with the WA Nonprofit Corporation Act, Chapter 24.03A RCW.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section B, line 11b</FormAndLineReferenceDesc>
        <ExplanationTxt>Each member of the Board of Governors is given a copy of the Form 990 prior to its submission.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section B, line 12c</FormAndLineReferenceDesc>
        <ExplanationTxt>All Board members and officers of ARC are covered by a Conflict of Interest Policy. There are bi-annual reviews of the individual Conflict of Interest statements by the governance committee, which determines whether a conflict exists. All statements are kept on file. Board members are expected to disclose conflicts as they may arise on the honor system, with the oversight of the governance committee. If a conflict exists or arises during the course of the business, the governance committee investigates and determines any action to take in accordance with the policy. This may include a member being prohibited from participating in the deliberations and decisions with respect to the transaction.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section C, line 19</FormAndLineReferenceDesc>
        <ExplanationTxt>ARC makes governing documents available to the public upon request.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleO>
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