49 CFR 1144.1: Negotiation.

(a) Timing. At least 5 days prior to seeking the prescription of a through route, joint rate, or reciprocal switching, the party intending to initiate such action must first seek to engage in negotiations to resolve its dispute with the prospective defendants.

(b) Participation. Participation or failure to participate in negotiations does not waive a party's right to file a timely request for prescription.

(c) Arbitration. The parties may use arbitration as part of the negotiation process, or in lieu of litigation before the Board.