Where proof of service is required by statute or rule, filing the papers with the board, together with one of the following, shall constitute proof of service:

1. (1) an acknowledgement of service
2. (2) A certificate that the person signing the certificate served the papers upon all parties of record in the proceeding by delivering a copy thereof in person to (names).

3. (3) A certificate that the person signing the certificate served the papers upon all parties of the proceeding by:

   1. (a) Mailing a copy thereof, properly addressed with the postage prepaid, to each party to the proceeding or his or her attorney or authorized agent; or
   2. (b) Transmitting a copy thereof by fax, and on the same day mailing a copy, to each party to the proceeding or his or her attorney or authorized agent; or
   3. (c) Depositing a copy thereof, properly addressed with charges prepaid, with a commercial parcel delivery company.

[Statutory Authority: RCW 41.24.290(2). WSR 13-21-050, § 491-04-140, filed 10/11/13, effective 11/11/13.]