Jonathan Singer of Fish & Richardson.

The medical diagnostics industry is making one more push to protect its technology from Section 101 patent eligibility challenges, but seemed to hit a familiar brick wall Thursday at the U.S. Court of Appeals for the Federal Circuit.

Athena Diagnostics, Oxford University and the Max Planck Institute accuse the Mayo Clinic of infringing their 7,267,820 patent on a technique for diagnosing the neuromuscular disease myasthenia gravis. U.S. District Judge Indira Talwani of Massachusetts ruled the patent ineligible on the ground that Athena, a subsidiary of Quest Diagnostics Inc., had patented a law of nature.

Athena Diagnostics v. Mayo Collaborative Services arrived at the Federal Circuit on Thursday with amicus support from the Biotechnology Innovation Organization, law professors and practicing attorneys. BIO argues U.S. Supreme Court and Federal Circuit case law have created “unabated uncertainty” about the patent eligibility of biotech inventions, especially in the diagnostics area.

➤➤ Get IP news and commentary straight to your inbox with Scott Graham's email briefing, Skilled in the Art. Learn more and sign up here.

Fenwick & West partner Adam Gahtan told the court Talwani oversimplified the asserted patent claims, which involve using recombinant DNA technology to create fragments of a protein known as MuSK. “The specification goes into great detail about how the inventors found the binding sites on this very complex, enormous, trans-membrane protein,” Gahtan said.

Judge Alan Lourie sounded skeptical. “Counsel, these claims are awfully simple,” he told Gahtan. “It's not clear to me how they differ from the other Mayo case,” he said, referring to the Supreme Court's landmark eligibility decision Prometheus v. Mayo.

Gahtan argued that the fragments are nonnatural and must be used in a concrete, specific way. The mere presence of a natural phenomenon such as the entire MuSK protein doesn't automatically invalidate the claim, he argued.

Fish & Richardson partner Jonathan Singer argued for Mayo that the only novelty arguably present is the natural relationship between MuSK and myasthenia gravis, and that relationship can't be patented.

“This court and other courts have been through this,” Singer said. “I've been through this court arguing that the use of a non-natural material made something patentable, and that argument was rejected in the BRCA case. That simply doesn't get you over the hurdle.”

Judge Pauline Newman told Singer the plaintiffs made “a powerful point.” Their patent represents “an advance in the science over precedent. But you're saying because these are natural products, that ends it. Why would anyone do this research in that case?”

Singer pointed to Ariosa Diagnostics v. Sequenom, a Federal Circuit decision involving the discovery of fetal DNA. It was undisputed that was “a remarkable discovery,” but it still wasn't patentable, he said.

“The patent system has an incentive effect, there's no doubt about it,” Singer said. “At the same time, the Supreme Court has cautioned … we shouldn't tie up the basic tools of scientific research purely for that incentive effect.”