In its June 12, 2015 opinion in Ariosa Diagnostics, Inc. v. Sequenom, Inc., the U.S. Court of Appeals for the Federal Circuit held that Sequenom's patent directed to methods of detecting fetal DNA in a pregnant woman's plasma or serum, although "a positive and valuable contribution to science," was not eligible for patent under U.S. Supreme Court precedent. Ariosa Diagnostics, Inc. v. Sequenom, Inc., Case Nos. 2014-1139, 2014-1144, slip op. at 16 (Fed. Cir. June 12, 2015) ("Ariosa"). The Federal Circuit's decision underscores the breadth of the Supreme Court's test, originally announced in Mayo Collaborative Serv. v. Prometheus Labs. Inc., 132 S. Ct. 1289 (2012), for distinguishing patents that impermissibly claim laws of nature, natural phenomena, and abstract ideas from those that claim patent-eligible applications of those concepts.

In 1996, scientists discovered the presence of cell-free fetal DNA ("cffDNA") in maternal plasma and serum, the portion of maternal blood others in the field had been routinely discarding as medical waste. Ariosa, slip op. at 3. Applying certain laboratory techniques, the scientists were able to detect the small fraction of cffDNA that was inherited from the father, enabling them to determine fetal genetic characteristics. The ability to detect cffDNA in the maternal circulation revolutionized the field of prenatal DNA testing by avoiding the clinical risks inherent in the invasive standard-of-care tests at the time, which relied on taking DNA samples from the fetus or placenta. Id.Sequenom obtained an exclusive license to the first patent directed to the discovery of cffDNA—U.S. Patent. No. 6,258,540 (the "'540 patent"). Claim 1 of the '540 patent, the broadest independent claim, claimed a method of "amplifying a paternally inherited nucleic acid from the [maternal] serum or plasma sample" and "detecting the presence of a paternally inherited nucleic acid of fetal origin." Id. at 4.

In 2011, Sequenom sought to enforce the '540 patent against several competitors, including Ariosa. In response, Ariosa filed a declaratory judgment action in the U.S. District Court for the Northern District of California. On the parties' cross-motions for summary judgment, the district court held that the '540 patent was invalid under §101. Id. at 7. Sequenom appealed to the Federal Circuit. Like the district court, the Federal Circuit applied the familiar two-step framework for analyzing claims under §101 announced by the Supreme Court in MayoId. at 8. Under the first step, the court must determine whether the claim at issue is directed to a patent-ineligible concept, such as a law of nature, natural phenomenon, or abstract idea. Id. If so, the court turns to the second step of the Mayo test, which requires the court to determine whether the additional elements of the claim amount to an "inventive concept" sufficient to "'transform the nature of the claim' into a patent-eligible application." Id. (quoting Mayo, 132 S. Ct. at 1298).

Applying this test to Sequenom's patent claims, the Federal Circuit held that under step one of Mayo, the claims of the '540 patent were "generally directed to detecting the presence of a naturally occurring thing or a natural phenomenon, cffDNA in maternal plasma or serum." Id. at 10. Turning to step two, the court held that the additional steps in each claim, such as amplifying and detecting cffDNA through polymerase chain reaction, were all well-understood, routine, and conventional activity at the time of filing of the '540 patent in 1997. Id. at 11. Thus, "[t]he only subject matter new and useful as of the date of the application was the discovery of the presence of cffDNA in maternal plasma or serum." Id. According to the court, this was not sufficient to satisfy the second step of the Mayo analysis, and it affirmed the district court that the claims were invalid under §101. Id.at 13.

The Federal Circuit did not end its discussion there. It took the opportunity to address an important issue regarding preemption. Sequenom had argued that because the record clearly showed that the '540 patent did not preempt all uses of cffDNA, the claims should be upheld. Id. at 14. The Federal Circuit acknowledged that "the principle of preemption is the basis for the judicial exceptions to patentability" but held that "questions on preemption are inherent in and resolved by the §101 analysis." Id. In other words, "[w]here a patent's claims are deemed only to disclose patent-ineligible subject matter under the Mayo framework, as they are in this case, preemption concerns are fully addressed and made moot." Id. at 14–15.

In a separate concurring opinion, Judge Linn highlighted the consequences of the Supreme Court's test in Mayo and expressed his concerns that theMayo test is too sweeping. Ariosa, concurring op. at 4–5. Judge Linn wrote that he would have held the '540 patent valid under §101 if the Federal Circuit were not bound by Supreme Court precedent, which "le[ft] no room to distinguish Mayo from this case." Id. at 3–5.

In conclusion, the Ariosa decision, including Judge Linn's concurring opinion, is important because it underscores the breadth of the Supreme Court'sMayo decision. It makes clear that "[g]roundbreaking, innovative, or even brilliant discovery does not by itself satisfy the §101 inquiry." Ariosa, slip op. at 16 (quoting Myriad Genetics, Inc., 133 S. Ct. 2107, 2117 (2013)). And, it holds that if a patent claim is invalid for failing Mayo's two-part test, any preemption concerns are fully addressed and rendered moot. Id. at 14–15.