An Am Law 50 firm was among the law firms that hit aircraft engine manufacturer Pratt & Whitney with an antitrust lawsuit on May 10 in a federal district court in Pennsylvania, accusing the company of trying to monopolize the U.S. market for two types of widely used turboprop engines.

Plaintiff Universal Turbine Parts LLC, a used aircraft engine supplier—represented by Quinn Emanuel Urquhart & Sullivan, White & Case; and Kohn, Swift & Graf—claimed in the lawsuit that the defendant, Pratt & Whitney, has worked to cut off the supply of used engines and parts in its PT6 and PW100 families of products in order to drive its competitors out of business.