The decision is expected to have an impact on the pharmaceutical industry.
The opinion written by Justice Stephen Breyer pointed to high court precedent: Although "laws of nature, natural phenomena and abstract ideas" are not patentable subject matter under ... the Patent Act," the ruling in 1981's Diamond vs. Diehr determined that "an application of a law of nature ... to a known structure or process may [deserve] patent protection."
"But to transform an unpatentable law of nature into a patent eligible application of such a law, a patent must do more than simply state the law of nature while adding the words 'apply it,' Breyer said.
The case involves Prometheus Laboratories Inc. of San Diego, exclusive licensee of two patents concerning "the use of thiopurine drugs to treat autoimmune diseases. When ingested, the body metabolizes the drugs, producing metabolites in the bloodstream."
Mayo Collaborative Services and Mayo Clinic Rochester (Minn.) bought and used diagnostic tests based on Prometheus' patents.
But in 2004 Mayo announced it intended to sell and market its own different diagnostic test. Prometheus sued Mayo contending Mayo's test infringed its patents. A federal judge ruled that the test infringed the patents but gave summary judgment to Mayo, saying the processes outlined in the patents effectively claim natural laws or natural phenomena (namely the correlations between thiopurine metabolite levels and the toxicity and efficacy of thiopurine drugs) and therefore are not patentable.
The Federal Circuit Court for the District of Columbia, which deals with intellectual property, reversed, finding the processes to be patent eligible.
But the Supreme Court reversed the appellate court, saying Prometheus' process is not patent eligible.