(a) Generally. Other than in cases under Final Offer Rate Review, which does not require the filing of an answer, an answer shall be filed within the time provided in paragraph (c) of this section. An answer should be responsive to the complaint and should fully advise the Board and the parties of the nature of the defense. In answering a complaint challenging the reasonableness of a rail rate, the defendant should indicate whether it will contend that the Board is deprived of jurisdiction to hear the complaint because the revenue-variable cost percentage generated by the traffic is less than 180 percent, or the traffic is subject to effective product or geographic competition. In response to a complaint filed under Simplified-SAC or Three-Benchmark, the answer must include the defendant's preliminary estimate of the variable cost of each challenged movement calculated using the unadjusted figures produced by the URCS Phase III program.

(b) Disclosure with Simplified-SAC or Three-Benchmark answer. The defendant must provide to the complainant all documents that it relied upon to determine the inputs used in the URCS Phase III program.

(c) Time for filing; copies; service. Other than in cases under Final Offer Rate Review, which does not require the filing of an answer, an answer must be filed with the Board within 20 days after the service of the complaint or within such additional time as the Board may provide. The defendant must serve copies of the answer upon the complainant and any other defendants.

(d) Cross complaints. A cross complaint alleging violations by other parties to the proceeding or seeking relief against them may be filed with the answer. An answer to a cross complaint shall be filed within 20 days after the service date of the cross complaint. The party shall serve copies of an answer to a cross complaint upon the other parties.

(e) Failure to answer complaint. Other than in cases under Final Offer Rate Review, which does not require the filing of an answer, averments in a complaint are admitted when not denied in an answer to the complaint.

(f) Discovery in stand-alone cost cases. Upon filing its answer, the defendant shall certify that it has served its initial discovery requests on the complainant. If the complainant tenders an amended or supplemental complaint to which the defendant must reply, upon filing the answer to the amended or supplemental complaint, the defendant shall certify that it has served on the complainant those initial discovery requests affected by the amended or supplemental complaint, if any.