By Stewart Bishop

Law360, New York (November 07, 2011, 9:03 PM ET) -- A Florida federal judge on Friday ruled in favor of Valeant Pharmaceuticals International Inc. in its patent dispute with Watson Pharmaceuticals Inc., finding that Valeant’s patents covering an antidepressant medication are valid.

U.S. District Judge Federico A. Moreno held that Watson failed to prove Valeant’s four patents covering the time-release antidepressant Aplenzin were invalid due to reasons of anticipation and obviousness.

Watson had sought to market a generic equivalent of Valeant’s version of the popular antidepressant Bupropion, and had conceded infringement but asserted as an affirmative...