A federal judge in Pittsburgh has taken the unusual step of tossing the class allegations from a suit brought by neighbors of a coal-fired power plant before they had even moved for class certification.

The suit, against the owner of the Cheswick Generating Station, had been revived by the U.S. Court of Appeals for the Third Circuit in the summer of 2013 when it ruled against the company's argument that adherence to regulations under the Clean Air Act would preempt the state-law tort claims brought by the neighbors. That was a matter of first impression for the appeals court.

On remand, the energy company sought to strike the class allegations from the complaint.