(b) By parties. All motions, petitions, pleadings, briefs or other documents shall be filed with the Office of Administrative Law Judges with a copy including any attachments to all other parties of record. When a party is represented by an attorney, service shall be made upon the attorney. Service of any document upon any party may be made by personal delivery or by mailing a copy to the last known address. The Department shall be served by delivery to the Associate Solicitor, Plan Benefits Security Division,
ERISA Section 502(i) Proceeding, P.O. Box 1914, Washington, DC 20013. The person serving the document shall certify to the manner and date of service.