The U.S. Supreme Court, in a 5-4 majority, held that the Federal Arbitration Act trumps a California rule invalidating as "unconscionable" a class action waiver provision in a cell phone arbitration agreement. The AT&T Mobility LLC v. Concepcion decision split the Court along ideological lines and drove consumer groups to call for congressional action on pending legislation that would ban mandatory arbitration agreements in most consumer and employment contracts.

However, Alan Kaplinsky, Chair of Ballard Spahr's Consumer Financial Services Group, who helped pioneer the use of consumer arbitration agreements with class action waivers, said: "I fully expected this result, but I have to say I am thrilled. It is important to note that this opinion doesn't mean that federal law will save an arbitration agreement that is unfair to consumers."