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        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION A, LINE 8B</FormAndLineReferenceDesc>
        <ExplanationTxt>THE GOVERNING BODY OF THE ORGANIZATION DOES NOT HAVE SEPERATE COMMITTEES. THEREFORE THIS IS NOT APPLICABLE.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 11B</FormAndLineReferenceDesc>
        <ExplanationTxt>A COPY OF THE 990 WILL BE PROVIDED TO THE FINANCE DIRECTOR, WHO WILL REVIEW THE 990 WITH THE BOARD OF DIRECTORS BEFORE IT IS FILED.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 12C</FormAndLineReferenceDesc>
        <ExplanationTxt>ALL MEMBERS OF THE BOARD OF DIRECTORS ARE COVERED UNDER THE ORGANIZATION'S CONFLICT OF INTEREST POLICY AND ALL BOARD OF DIRECTOR MEMBERS ARE INCLUDED IN THE DETERMINATION OF CONFLICTS OF INTEREST. ANY BOARD MEMBER WITH A CONFLICT OF INTEREST IS REQUIRED TO DISCLOSE BOTH ITS EXISTENCE AND ALL FACTS SURROUNDING THE CONFLICT TO THE BOARD. IF A BOARD MEMBER IS DETERMINED TO HAVE A CONFLICT OF INTEREST, HE OR SHE IS PROHIBITED FROM PARTICIPATING IN THE DELIBERATIONS AND DECISIONS RELATING TO CONFLICTING TRANSACTIONS.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 15</FormAndLineReferenceDesc>
        <ExplanationTxt>THE COMPENSATION OF ALL EMPLOYEES AND MANAGEMENT ARE APPROVED ON AN ANNUAL BASIS BY THE BOARD OF DIRECTORS. THE BOARD OF DIRECTORS USES COMPARABLE DATA, INCLUDING INDUSTRY STATISTICS AND GUIDESTAR.COM, TO DETERMINE COMPENSATION AMOUNTS.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION C, LINE 18</FormAndLineReferenceDesc>
        <ExplanationTxt>INFORMATION IS AVAILABLE ON GUIDESTAR AND UPON REQUEST.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION C, LINE 19</FormAndLineReferenceDesc>
        <ExplanationTxt>INFORMATION IS PRIVATE BUT COULD BE PROVIDED UPON REQUEST.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART XI, LINE 9:</FormAndLineReferenceDesc>
        <ExplanationTxt>INCOME FROM SUBSIDIARY 16,354.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleO>
    <IRS990ScheduleR documentId="RetDoc1043400001">
      <IdRelatedTaxExemptOrgGrp>
        <DisregardedEntityName>
          <BusinessNameLine1Txt>INSTITUTE OF PHYSICS</BusinessNameLine1Txt>
        </DisregardedEntityName>
        <ForeignAddress>
          <AddressLine1Txt>37 CALEDONIAN ROAD</AddressLine1Txt>
          <CityNm>LONDON</CityNm>
          <CountryCd>UK</CountryCd>
        </ForeignAddress>
        <PrimaryActivitiesTxt>SCIENTIFIC MEMBERSHIP ORGANIZATION</PrimaryActivitiesTxt>
        <LegalDomicileForeignCountryCd>UK</LegalDomicileForeignCountryCd>
        <ExemptCodeSectionTxt>N/A</ExemptCodeSectionTxt>
        <ControlledOrganizationInd>0</ControlledOrganizationInd>
      </IdRelatedTaxExemptOrgGrp>
      <IdRelatedTaxExemptOrgGrp>
        <DisregardedEntityName>
          <BusinessNameLine1Txt>IOP PUBLISHING LTD</BusinessNameLine1Txt>
        </DisregardedEntityName>
        <ForeignAddress>
          <AddressLine1Txt>TEMPLE CIRCUS TEMPLE WAY</AddressLine1Txt>
          <CityNm>BRISTOL</CityNm>
          <CountryCd>UK</CountryCd>
        </ForeignAddress>
        <PrimaryActivitiesTxt>PUBLISHING</PrimaryActivitiesTxt>
        <LegalDomicileForeignCountryCd>UK</LegalDomicileForeignCountryCd>
        <ExemptCodeSectionTxt>N/A</ExemptCodeSectionTxt>
        <ControlledOrganizationInd>0</ControlledOrganizationInd>
      </IdRelatedTaxExemptOrgGrp>
      <IdRelatedOrgTxblCorpTrGrp>
        <RelatedOrganizationName>
          <BusinessNameLine1Txt>IOP BUSINESS PUBLISHING INC</BusinessNameLine1Txt>
        </RelatedOrganizationName>
        <USAddress>
          <AddressLine1Txt>190 N INDEPENDENCE MALL WEST-SUITE</AddressLine1Txt>
          <CityNm>PHILADELPHIA</CityNm>
          <StateAbbreviationCd>PA</StateAbbreviationCd>
          <ZIPCd>19106</ZIPCd>
        </USAddress>
        <EIN>262301131</EIN>
        <PrimaryActivitiesTxt>SALE OF ADVERTISING</PrimaryActivitiesTxt>
        <LegalDomicileStateCd>PA</LegalDomicileStateCd>
        <EntityTypeTxt>C</EntityTypeTxt>
        <ShareOfTotalIncomeAmt>16354</ShareOfTotalIncomeAmt>
        <ShareOfEOYAssetsAmt>349800</ShareOfEOYAssetsAmt>
        <OwnershipPct>1.00000</OwnershipPct>
        <ControlledOrganizationInd>0</ControlledOrganizationInd>
      </IdRelatedOrgTxblCorpTrGrp>
      <ReceiptOfIntAnntsRntsRyltsInd>0</ReceiptOfIntAnntsRntsRyltsInd>
      <GiftGrntOrCapContriToOthOrgInd>0</GiftGrntOrCapContriToOthOrgInd>
      <GiftGrntCapContriFromOthOrgInd>0</GiftGrntCapContriFromOthOrgInd>
      <LoansOrGuaranteesToOtherOrgInd>1</LoansOrGuaranteesToOtherOrgInd>
      <LoansOrGuaranteesFromOthOrgInd>0</LoansOrGuaranteesFromOthOrgInd>
      <DivRelatedOrganizationInd>0</DivRelatedOrganizationInd>
      <AssetSaleToOtherOrgInd>0</AssetSaleToOtherOrgInd>
      <AssetPurchaseFromOtherOrgInd>0</AssetPurchaseFromOtherOrgInd>
      <AssetExchangeInd>0</AssetExchangeInd>
      <RentalOfFacilitiesToOthOrgInd>0</RentalOfFacilitiesToOthOrgInd>
      <RentalOfFcltsFromOthOrgInd>0</RentalOfFcltsFromOthOrgInd>
      <PerformOfServicesForOthOrgInd>0</PerformOfServicesForOthOrgInd>
      <PerformOfServicesByOtherOrgInd>0</PerformOfServicesByOtherOrgInd>
      <SharingOfFacilitiesInd>0</SharingOfFacilitiesInd>
      <PaidEmployeesSharingInd>0</PaidEmployeesSharingInd>
      <ReimbursementPaidToOtherOrgInd>0</ReimbursementPaidToOtherOrgInd>
      <ReimbursementPaidByOtherOrgInd>0</ReimbursementPaidByOtherOrgInd>
      <TransferToOtherOrgInd>0</TransferToOtherOrgInd>
      <TransferFromOtherOrgInd>0</TransferFromOtherOrgInd>
      <TransactionsRelatedOrgGrp>
        <OtherOrganizationName>
          <BusinessNameLine1Txt>IOP PUBLISHING LTD</BusinessNameLine1Txt>
        </OtherOrganizationName>
        <TransactionTypeTxt>D</TransactionTypeTxt>
        <InvolvedAmt>5673542</InvolvedAmt>
        <MethodOfAmountDeterminationTxt>SEE SCHEDULE O</MethodOfAmountDeterminationTxt>
      </TransactionsRelatedOrgGrp>
    </IRS990ScheduleR>
  </ReturnData>
</Return>