District of Columbia Code
Chapter 7 - Official Correspondence
§ 2–703. Marking requirements for envelopes

Envelopes or other materials which are used to enclose official mail shall bear upon its facing, in addition to the name and address of the agency mailing the official mail, the words “official business.”
(Apr. 7, 1977, D.C. Law 1-118, § 4, 23 DCR 8746.)
1981 Ed., § 1-1703.
1973 Ed., § 1-1703.
This section is referenced in § 2-704.