Last August, Kirkland & Ellis partner Paul Clement was minding his own business, not thinking much about arbitration or class actions. He was prepping for an important U.S. Supreme Court oral argument testing the scope of the Alien Tort Statute, set for October 11.

Then came the phone call from two fellow titans of the Supreme Court bar: Neal Katyal of Hogan Lovells and Kannon Shanmugam of Williams & Connolly. They represented employers in three high-profile cases before the high court, consolidated under the name of Epic Systems Corp. v. Lewis. The cases were all about whether arbitration agreements could preclude employees from resorting to class actions to resolve disputes in workplace disputes. The cases were scheduled to be argued on October 2.