A. The Commission or presiding officer may, whenever it deems desirable, require the filing of printed or typewritten briefs on behalf of any party or parties to an investigation, hearing, or other proceeding, and may fix the time for the filing of the briefs. Concurrent briefs are preferable. The briefs shall contain an abstract of the evidence and also the arguments relied on by the party or parties filing them.
B. A brief may not exceed 50 pages in length if produced by letterpress, multilith, or photo offset, or 60 pages in length if typewritten and reproduced by any other duplicating or copying process which produces a clear, readable black image on white paper, except by special permission of the Commission or presiding officer. This limitation does not apply to an appendix or to a table of contents and authorities. A brief of more than 20 pages shall contain a subject index and a table of authorities.
C. A request for an extension of time to file briefs shall be made in writing, and a copy of it served upon or mailed to the other parties to the proceeding. Ordinarily, when a matter has been submitted on concurrent briefs, extensions may not be granted unless a stipulation is filed with the Commission or presiding officer. The original of each brief shall contain a certification that copies have been served upon or mailed to each party or his attorney.
D. Unless otherwise prescribed or required by the Commission or presiding officer, each party to the proceeding shall file the original and a minimum of nine copies with the Commission or presiding officer.