Lawyers for Airgas and its former law firm, Cravath Swaine & Moore, didn’t show up in Philadelphia Commerce Court Tuesday for a planned preliminary injunction hearing because the law firm removed the case to federal court.

Cravath and Radnor, Pa.-based Airgas will now battle in U.S. District Court for the Eastern District of Pennsylvania over whether Cravath properly terminated its relationship with Airgas in order to represent competitor Air Products & Chemicals in Air Products’ $5.1 billion offer to acquire Airgas. Both companies, which are involved in the distribution of industrial, medical and specialty gases, have been longtime clients of Cravath.