Shares of Bristol-Myers (BMY -0.7%) slide after a federal judge rules a U.S. patent for its...

|About: Bristol-Myers Squibb Company (BMY)|By:, SA News Editor

Shares of Bristol-Myers (BMY -0.7%) slide after a federal judge rules a U.S. patent for its hepatitis B treatment Baraclude is invalid, saying there's clear and convincing evidence that a key claim in the patent is invalid due to obviousness. The ruling opens the door to Teva Pharmaceutical (TEVA +0.4%) selling a competing generic copy. BMY says it's disappointed in the ruling and plans to appeal.