* Bristol-Myers says considering whether to appeal decision * Bristol shares slip 0.6 pct, Teva falls 0.4 percent Feb 12 (Reuters) - A U.S. federal court has invalidated the U.S. patent on Bristol-Myers Squibb Co's Baraclude treatment for hepatitis B after a challenge from generic drugmaker Teva Pharmaceutical Industries Ltd, Bristol-Myers said on Tuesday. "We are disappointed with the court's decision and believe it is incorrect," Bristol-Myers spokeswoman Laura Hortas said. She said the company is considering whether to appeal the ruling by the U.S. District Court in Delaware. Bristol-Myers had filed suit against Israeli drugmaker Teva in 2010 to block introduction of its generic form of Baraclude. Hortas said the drug's chemical patent lapses in February 2015, but declined to comment on whether U.S. regulators might allow Teva's generic onto the market before then. Teva officials could not immediately be reached for comment. ISI Group analyst Mark Schoenebaum said the U.S. Food and Drug Administration would have to approve Teva's marketing application before its generic could be introduced, and that it was unclear when the FDA might act. Schoenebaum said Baraclude is expected to have U.S. sales this year of about $260 million. Even if the Teva generic arrives this year and hurts Baraclude's U.S. sales, he said Bristol-Myers will probably not need to lower its current full-year profit forecast. Shares of Bristol-Myers were down 0.6 percent at $36.69 on the New York Stock Exchange on Tuesday morning. Teva shares were down 0.4 percent in Tel Aviv.