D.C. Mun. Regs. tit. 27, r. 27-108
Except as otherwise provided in the Board's rules or directed by an administrative judge, a pleading, motion, notice, appearance, or other submission filed with the Board subsequent to the filing of an appeal or a protest, shall be served by the filing party upon each party in the case.
Whenever, under this Rule or a Board order, service is required or permitted to be made upon a party who is represented by an attorney, the service shall be made upon the attorney.
Electronic service upon a party shall be as provided in Chapter 4. Non-electronic service upon a party, or an attorney representing a party, shall occur at the time of hand delivery; or, if by mail, to the address of record, by the postmark date plus three days as prescribed in Section 122.
The Board may waive the requirement of furnishing to other parties copies of bulky, lengthy, or out-of-size documents when the party, by written motion, has shown that service would impose an undue burden. The moving party shall notify the other parties that the documents are available for inspection at the office of the Board.
Notwithstanding the foregoing, any document may be served electronically pursuant to Chapter 4.
D.C. Mun. Regs. tit. 27, r. 27-108