Opalinski v. Robert Half International, Inc.

Whether, where an arbitration agreement does not expressly refer to class arbitration, the determination of whether class or group arbitration is permitted by the agreement is a question of arbitrability, presumptively for the district court to decide (as the Third and Sixth Circuits have now held), or a question of interpretation and procedure for the arbitrator (as the First, Second, Seventh, and Eleventh Circuits, and numerous district courts have concluded).