"The message is, 'We're not prejudging what the outcome should be in this case but we don't think you've analyzed it in the right way,'" said Nick Groombridge, a patent lawyer with Paul Weiss in New York who also teaches law at Columbia and Rutgers Universities.
The March 20 decision involved a dispute between Nestle SA's Prometheus unit and units of the Mayo Clinic and whether certain types of diagnostic tests met the threshold of eligibility for a patent. A June 2010 decision by the Supreme Court also addressed what types of inventions qualify for legal protection.
The Myriad case pits the biotechnology industry, which supports gene patents, against an array of opponents including doctors, researchers and patients who say gene patents will stifle innovation and improperly permit a monopoly on part of the human body. The case affects the field of personalized medicine, in which doctors determine whether a patient is susceptible to a particular disease or would be more responsive to certain medications.
"The question of whether human genes and the information they convey are patentable is of paramount importance to the future of patent law, the advancement of medical science and patients' health," the challengers to the Myriad patents argued in their appeal.
The group, whose legal team includes the American Civil Liberties Union, is pressing a test case against Salt Lake City- based Myriad. The company makes tests for the hereditary risk of breast and ovarian cancer.
The Prometheus patents "excluded too many other people from developing new things," said James Mullen, a patent lawyer with Morrison & Foerster in San Diego who specializes in helping biotechnology companies obtain patents. He said that the Supreme Court's decision to have the Federal Circuit look at the patents anew is good news for patents on gene-related technology.
"If they wanted to put a stake through the heart of these claims, they'd do it," Mullen said. "If they delve into isolated DNA claims, they would have the ability to disrupt and cripple biotechnology across the board."
About 20 percent of human genes have some level of patent protection, according to a 2005 article in Science magazine. The biotechnology industry says patents let it attract venture capital to pay for research into new medicines and the causes of diseases.
The central legal issue is whether so-called isolated DNA - - genetic coding that has been removed from the body and separated from other material is a product of nature and thus ineligible for patent protection under previous Supreme Court rulings.
In the March 20 decision, Justice Stephen Breyer wrote for a unanimous court in warning against "tying up the use of the underlying natural laws."
"To the extent that actual politics intrude on the thought process of the Supreme Court, I wonder if they're not concerned with patent policy that results in an increase in costs to patients," Mullen said.
Genes are encoded strands of nucleotides in different sequences that are responsible for inherited traits. In isolating genes, Myriad strips out unneeded information to home in on aspects that determine whether a person has a higher risk of breast and ovarian cancer.
In court papers, Myriad said that "human intervention" brings isolated DNA within the scope of the U.S. patent laws. The company says the U.S. Patent and Trademark Office has issued 2,645 patents for isolated DNA over the past 30 years.
The case is Association for Molecular Pathology v. Myriad Genetics, 11-725.