All claims, resubmitted claims, petitions to intervene and rulings thereon, notices of oral hearings, notices of oral arguments (if necessary), decisions of the administrative law judge, notices of review, and Commission decisions shall be served by the administrative law judge or the Commission. All other pleadings, documents and filings shall, when tendered to the Commission, evidence service upon all parties to the proceeding. Such certificate shall be in substantially the following form:
I hereby certify that I have this day served the foregoing document upon all parties of record in this proceeding by [mailing, delivering to courier, or delivering in person], a copy to each such person in sufficient time to reach such person on the date the document is due to be filed with the Commission.
Dated at __________ this ________ day of _________, 19__.
(Signature)
(For)
[Rule 320.]