The Supreme Court ruled on Wednesday for an AT&T Inc unit seeking to require arbitration for a dispute over cell phone taxes rather than allowing customer claims to be brought together in a class-action lawsuit.

The justices overturned a ruling by a U.S. appeals court that declared unenforceable under California law a provision in AT&T Mobility's customer contracts that required all disputes to be settled by arbitration and that prevented the pooling of claims in a class-action lawsuit.

(Reporting by James Vicini, Editing by Gerald E. McCormick)