Latham & Watkins is fighting to remain lead trial counsel for a freight rail company in a case billed as one of the largest antitrust matters of all time.

Four of the top freight rail companies in the country are accused of orchestrating a scheme to raise customer rates through fuel surcharges. One of the defendants, Union Pacific Railroad Co., hired Latham in October — to the dismay of ex-Latham clients who are plaintiffs in the case.