15 C.F.R. § 906.5 – Service.

(a) Service refers to providing documents to parties to an appeal.
1. (1) Service of documents may be made by first class mail (postage prepaid), facsimile, or commercial carrier, or by personal delivery to a party's address of record.
2. (2) Service of documents will be considered effective upon the date of postmark (or as otherwise shown for government-franked mail), facsimile transmission, delivery to a commercial carrier, or upon personal delivery.
(b) A party shall serve a copy of all documents to all other parties and shall file a copy of all documents with NAO the same business day.
(c) NAO may serve documents by electronic mail.