(a) Parties to a proceeding. Any interested person may become a party to proceedings docketed for a hearing on the record by filing a notice of intervention. The Postal Service, and the Public Representative are automatically deemed parties in such proceedings without the need to file a notice of intervention. Persons who file a complaint are also automatically deemed a party to a complaint proceeding without the need to file a notice of intervention. Parties may be provided an opportunity to participate in discovery, file testimony, participate in the written or oral examination of witnesses, file briefs, or present oral argument before the Commission or the presiding officer. Persons that have not intervened may participate in a proceeding docketed for a hearing on the record, but such participation shall be limited to providing comments pursuant to § 3010.140 unless otherwise directed.

(b) Notices of intervention. A notice of intervention shall clearly and concisely set forth the nature and extent of the intervenor's interest in the issues to be decided, including the postal services utilized by the intervenor giving rise to the intervenor's interest in the proceeding, and to the extent known, the position of the intervenor with regard to the proposed changes in postal rates, fees, classifications, or services, or the subject matter of the complaint, as described in the notice of the proceeding. Such notice shall state whether or not the intervenor requests a hearing or in lieu thereof, a conference, and whether or not the intervenor intends to actively participate in a hearing. Such notice shall also include on page one thereof the name and full mailing address of no more than two persons who are to receive service, when necessary, of any documents relating to such proceeding.

(c) Form and time of filing. Notices of intervention shall be filed no later than the date fixed for such filing by the Commission or its Secretary, unless for good cause shown, the Commission authorizes a late filing. Without a showing for good cause, late intervenors shall be subject to and may not challenge decisions by the Commission or presiding officer made prior to acceptance of the request for late intervention.

(d) Oppositions. (1) Except as otherwise provided in paragraph (d)(2) of this section, oppositions to notices of intervention may be filed by any party in the proceeding no later than ten days after the notice of intervention is filed.

(2) Oppositions to notices of interventions in proceedings considering the change in the nature of a postal service pursuant to part 3020 of this chapter may be filed by any party in the proceeding no later than three days after the notice of intervention is filed.

(3) Pending Commission action, an opposition to intervention shall, in all proceedings except those considering the change in the nature of a postal service pursuant to part 3020 of this chapter, delay on a day-for-day basis the date for responses to discovery requests filed by that intervenor.

(e) Effect of intervention. A person filing a notice of intervention shall be a party to the proceeding subject, however, to a determination by the Commission, either in response to an opposition, or sua sponte, that party status is not appropriate under the Act. Intervenors are also subject to the right of the Commission or the presiding officer as specified in § 3010.104 to require two or more intervenors having substantially like interests and positions to join together for purposes of service of documents, presenting evidence, making and arguing motions and objections, propounding discovery, cross-examining witnesses, filing briefs, and presenting oral arguments to the Commission or presiding officer. No intervention shall be deemed to constitute a decision by the Commission that the intervenor is aggrieved for purposes of perfecting an appeal of any final order of the Commission.