A key question in enforcing arbitration agreements in class actions is whether arbitration will proceed on an individual or class basis. But who will answer that question – the court or the arbitrator? The Fourth Circuit recently held that, absent clear and unmistakable language in the arbitration agreement to the contrary, that threshold question about the availability of class arbitration is for the court to decide. For more about the Fourth Circuit’s decision (and why it’s a win for businesses invoking arbitration agreements), see the report on Mayer Brown’s Class Defense blog by my partners Archis A. Parasharami, Kevin Ranlett, and Charles E. Harris II.