The company at the heart of the Martha Stewart stock scandal is in the midst of a bitter patent dispute that threatens its bottom line and has led some world-renowned cancer researchers into a courtroom for a highly unusual showdown.

A judge in Manhattan federal court is deciding who is the rightful owner of a patent used for ImClone Systems Inc.’s blockbuster cancer drug Erbitux. A team of three esteemed scientists from Israel who pioneered a cancer treatment technique claim a former colleague stole their idea and was credited on a patent now owned by Aventis Pharmaceuticals Inc. and licensed to ImClone.