Opalinski v. Robert Half International, Inc.

Issue: 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).