D.C. Mun. Regs. tit. 31, § 712
712.1 Each written compliance order issued pursuant to § 702, each enforcement action authorized by § 703 other than an order of impoundment of a vehicle, and each invitation to mediate issued pursuant to § 711, shall be served by one of the following methods, unless a different method of service is required by law:
(a) By personal service upon the respondent or the respondent's agent, through delivery of the document to the last known home or business address of the respondent, or the respondent's agent, on file with the Office and leaving the document with a person over the age of sixteen (16) years old residing or employed at that address by handing the notice or order to such individual;
(b) By posting the document in a conspicuous place in or about the location of respondent's place of business; or
(c) By depositing the document into first-class U.S. Mail, addressed to the last known home or business address of the respondent, or respondent's agent, on file with the Office.
712.2 Service pursuant to § 712.1(c) is complete at the time the document is deposited into the U.S. Mail, regardless of whether an earlier or later date or time is stamped upon the envelope.
712.3 An individual licensed by the Commission who defaces, alters, or removes a document posted pursuant to § 712.1 (b) without the approval of the Office shall be subject to a civil fine in the amount of one thousand dollars ($1,000).
712.4 An entity licensed by the Commission that allows or induces an individual to deface, alter, or remove a document posted pursuant to § 712.1(b), without the approval of the Office, shall be subject to a civil fine in the amount of two thousand five hundred dollars ($2,500).
712.5 Each document subject to service under § 712.1, other than a compliance order or invitation to mediate, shall be filed promptly with OAH in the manner prescribed by its rules and procedures.
SOURCE: Final Rulemaking published at 61 DCR 6408 (June 27, 2014).