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      <Form990ScheduleAPartVIGrp>
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      <Form990ScheduleAPartVIGrp>
        <FormAndLineReferenceDesc>Schedule A, Part III:</FormAndLineReferenceDesc>
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        <ExplanationTxt>Monitoring is provided by the Chilren's Hospital Pathology Foundation, Inc. (the Foundation) through oversight of the terms and conditions of a written grant agreement. Multiyear agreements require yearly progress and financial reports for continuation of funding. During the year ended September 30, 2018, the Foundation only provided grant donations to other 501(c)(3) organizations.</ExplanationTxt>
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        <PersonNm>Lisa Anne Teot MD</PersonNm>
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        <PersonNm>Jeffrey Goldsmith MD</PersonNm>
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        <PersonNm>Olga K Weinberg MD</PersonNm>
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        <TotalCompensationFilingOrgAmt>459508</TotalCompensationFilingOrgAmt>
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      <RltdOrgOfficerTrstKeyEmplGrp>
        <PersonNm>Sara O Vargas MD</PersonNm>
        <TitleTxt>Physician</TitleTxt>
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        <PersonNm>Hart GW Lidov MD</PersonNm>
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        <PersonNm>Marian Harris MD</PersonNm>
        <TitleTxt>Physician</TitleTxt>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, Line 1a</FormAndLineReferenceDesc>
        <ExplanationTxt>The Foundation provides reimbursement for health club fees. All individuals listed in Form 990, Part VII received this benefit and the reimbursement is included as part of taxable wages to each recipient. The Foundation discontinued offering this benefit in March of 2017.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, Line 7</FormAndLineReferenceDesc>
        <ExplanationTxt>The method for calculation bonus payments is a percentage of the individual's salary. However, the Chairman can change the bonus amount based on a number of factors including but not limited to, the following: clinical workload adjustments; teaching responsibilities; academic performance; administrative responsibilities; and/or special circumstances. The bonus amounts are discretionary.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleJ>
    <IRS990ScheduleO documentId="RetDoc1044400001">
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 1</FormAndLineReferenceDesc>
        <ExplanationTxt>A majority of the Children's Hospital Pathology Foundation, Inc.'s (the Foundation's) board members are physicians who are not independent of the Foundation. However, the Foundation participates in an integrated delivery system with Boston Children's Hospital (the Hospital) which does have a community board. The Foundation was organized in 1990. At that time, the board was composed entirely of physicians, a board structure that was approved by the Internal Revenue Service. The Foundation has since adjusted the board structure to make it more responsive to the Hospital by adding the Physicians Organization at Children's Hospital, Inc. (the PO) as a member. See Schedule O, Part VI, Questions 3, 6, 7b, and 12 for more details on the PO's rights.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 3</FormAndLineReferenceDesc>
        <ExplanationTxt>The Physicians Organization at Children's Hospital, Inc. (the PO) is the Class "C" member of Children's Hospital Pathology Foundation, Inc. (the Foundation). The PO is responsible for providing management services to the Foundation. The PO has the power to approve the independent auditor and legal counsel of the Foundation from a list of firms mutually agreed to by the PO and the Foundation. The PO also has the right to review, but not to approve, the annual budgets and by-law changes of the Foundation. Lastly, Boston Children's Hospital has the right to review for compliance with applicable laws, the general terms of and any modification to physician compensation and benefit plans for all physician employees of the Foundation.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 6</FormAndLineReferenceDesc>
        <ExplanationTxt>The Children's Hospital Pathology Foundation, Inc. (the Foundation) has three classes of members. The Chairman of the Department of Pathology (the Department) of Boston Children's Hospital (the Hospital) is the Class "A" member. Any member of the Department (other than the Chairman) who holds a medical staff appointment from the Hospital, has a full-time faculty appointment from Harvard University Medical School, and who has entered into a written agreement with and receives compensation from the Foundation shall be a Class "B" member. Individuals engaged in clinical or research matters in the field of pathology at the Hospital may request membership and can be Class "B" members if invited by the Chairman and ratified by the Class "B" members. The Physicians Organization at Children's Hospital, Inc. is the Class "C" member of the Foundation.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 7a</FormAndLineReferenceDesc>
        <ExplanationTxt>According to the Articles of Organization, the Class "A" member is the Chairman of the Department of Pathology (the Department) of Boston Children's Hospital (the Hospital). Any member of the Department who holds a medical staff appointment from the Hospital, has a full-time faculty appointment from Harvard Medical School, and who has entered into a written employment agreement and receives compensation from the Hospital shall be a Class "B" member. Class "A and "B" members hold their membership as long as they remain qualified for membership. Only Class "A and "B" members may vote at their annual meeting or other elections, serve on the Children's Hospital Pathology Foundation, Inc.'s Board, or may nominate candidates for election to the Board.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 7b</FormAndLineReferenceDesc>
        <ExplanationTxt>The Physicians Organization at Children's Hospital, Inc. (the PO) is the Class "C" member of Children's Hospital Pathology Foundation, Inc. (the Foundation). The PO is responsible for providing management services to the Foundation. The PO has the power to approve the independent auditor and legal counsel of the Foundation from a list of firms mutually agreed to by the PO and the Foundation. The PO also has the right to review, but not to approve, the annual budgets and by-law changes of the Foundation. Lastly, Boston Children's Hospital has the right to review for compliance with applicable laws, the general terms of and any modification to physician compensation and benefit plans for all physician employees of the Foundation. As the Class "C" member of the Foundation, the PO attends the Foundation's annual meeting.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section B, line 11b</FormAndLineReferenceDesc>
        <ExplanationTxt>The detailed review will be conducted by the President of the Foundation, Mark D. Fleming, MD and the administrator, John Baci. A copy of Form 990 will be provided to the governing board prior to filing. The detailed review will be conducted before filing the return with the Internal Revenue Service.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section B, line 12c</FormAndLineReferenceDesc>
        <ExplanationTxt>The Physicians Organization at Children's Hospital, Inc. (the PO) and Boston Children's Hospital (the Hospital) administer an annual conflict of interest disclosure process to all of their member Foundations, which asks physicians (officers, top management, and highly compensated employees) and selected Foundation staff to disclose potential conflicts. A disclosure statement will be circulated annually to members of the PO. The audit committee shall determine those individuals (including medical staff members) who shall be required to complete the disclosure statement. The audit committee, at its discretion, may either: 1) refer any or all statements to the Board of Directors; 2) appoint an ad hoc committee to review and resolve any conflicts of interest issues; or 3) review and resolve any conflict of interest personally or through a designee(s). Any person not receiving a disclosure statement has an affirmative obligation to disclose to the PO President, PO General Counsel, or his/her supervisor whenever he/she believes he/she has or may have a conflict of interest. Similarly, each person completing a disclosure statement has an affirmative obligation to update the statement any time circumstances change and/or he/she believes that a conflict of interest may exist. In the event a conflict of interest is found to exist, the Foundation prohibits the member from voting on any matter to which the conflict relates or otherwise influence the voting on such matter.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section B, line 15</FormAndLineReferenceDesc>
        <ExplanationTxt>Faculty compensation must comply with the Boston Children's Hospital (the Hospital) Physician Compensation Guidelines. These guidelines are developed in consultation with an independent external compensation consulting firm and are approved by the independent Compensation Committee of the Board of Children's Medical Center Corporation and the Hospital. The guidelines set the maximum compensation limits based on a peer group analysis for the Foundation. The maximum compensation limits are based on pediatric specialty, sub-specialty, academic rank, and include productivity adjustments. Any proposed compensation that exceeds the limits must be prospectively approved by the independent compensation committee of the Board of the Hospital. Annual compensation for individual faculty members is set by the President of Children's Hospital Pathology Foundation, Inc. (the Foundation), reviewed and approved by the Foundation in accordance with the Foundation's compensation policies and procedures. The Foundation's President's compensation is reviewed and approved annually on a prospective basis by the Hospital's Chief Executive Officer and President/Chief Operating Officer.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section C, line 19</FormAndLineReferenceDesc>
        <ExplanationTxt>The Foundation maintains all financial records, conflict of interest policies, and governing documents at its main office at 300 Longwood Avenue, Boston, MA 02115. The documents are available upon request.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part XII, Line 2c:</FormAndLineReferenceDesc>
        <ExplanationTxt>The audit process and scope has not changed from the prior year.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleO>
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