A U.S. Federal Court of Appeals has ruled that Prometheus Laboratories' test for determining the proper dose of a drug for a specific patient with certain gastrointestinal ailments is patentable. Prometheus had charged in a lawsuit that the Mayo Clinic infringed on two of its patents underlying its test, but a lower court ruled the patents were invalid because they failed to meet the standards of what is patentable. The decision comes at a time of heightened legal activity around the question of patentability for diagnostics. We spoke to Ken Chahine, visiting professor of law at the University of Utah, about the ruling, what it means for the diagnostics industry, and what effect it will have on other cases winding their way through the courts.