The Third Circuit reined in runaway readings of its recently adopted standard for assessing class action cases Thursday.

Although the court clarified that evaluating the ascertainability of a class requires a narrow inquiry, Judge Marjorie O. Rendell warned in a concurring opinion that the majority didn't go far enough.

The U.S. Court of Appeals for the Third Circuit adopted the ascertainability standard for district courts assessing potential class actions in 2012 with its opinion in Marcus v. BMW of North America. A year later, it issued another, more controversial opinion on the issue, Carrera v. Bayer.