Supreme Court seems divided in patent dispute over best-selling multiple sclerosis drug

The Supreme Court seems divided as it considers a high-stakes patent dispute between rival pharmaceutical companies over the world's best-selling multiple sclerosis treatment.

Justices heard arguments Wednesday in a case that threatens to cut into the $4 billion-a-year profits that Israel-based Teva Pharmaceutical Industries Ltd. earns selling the drug Copaxone.

Teva claims the U.S. Court of Appeals for the Federal Circuit wrongly overturned five of its patents for the drug. At issue is whether the appeals court was allowed to second-guess factual findings made by a federal district court that had earlier ruled in Teva's favor.

The justices seemed split over whether patent cases should be reviewed under a different standard than other cases, where appeals courts must defer to factual findings made by lower courts.