Section 405.1843 - Parties to proceedings in a Board appeal(a)(1) When a provider files a request for a hearing before the Board in accordance with § 405.1835 or § 405.1837 , the parties to all proceedings in the Board appeal include the provider, a contractor, and, where applicable, any other entity found by the Board to be a related organization of the provider under the principles enunciated in § 413.17 of this chapter.(2) All parties to a Board appeal are to familiarize themselves with the instructions for handling a Provider Reimbursement Review Board (PRRB) appeal, including any and all requirements related to the electronic/online filing of documents.(b) Neither the Secretary nor CMS may be made a party to proceedings in a Board appeal. (1) The Board may call as a witness any employee or officer of the Department of Health and Human Services or CMS having personal knowledge of the facts and the issues in controversy in an appeal.(2) The regulations at 45 CFR Part 2 (Testimony by employees and production of documents in proceedings where the United States is not a party) apply as to whether such employee or officer will appear.(c) A contractor may designate a representative from the Secretary or CMS, who may be an attorney, to represent the contractor in proceedings before the Board.(d) Although CMS is not a party to proceedings in a Board appeal, there may be instances where CMS determines that the administrative policy implications of a case are substantial enough to warrant comment from CMS (as described in § 405.1863 of this subpart). CMS- (1) May file amicus curiae (friend of the court) briefing papers with the Board in accordance with a schedule to be determined by the Board.(2) Must promptly send copies of any documents filed with the Board to each party to the appeal.(e) A nonparty other than CMS may seek leave from the Board to file amicus curiae briefing papers with the Board.(f) The Board may exclude from the record all or part of an amicus curiae briefing paper. When the Board excludes from the record all or part of an amicus curiae briefing paper submitted by CMS, it states for the record its reason(s) in writing. 73 FR 30256 , May 23, 2008, as amended at 85 FR 59019 , Sept. 18, 2020