The Federal Circuit Friday held in Ariosa Diagnostics, Inc. v. Sequenom, Inc. that Sequenom’s patent directed toward its MaterniT21 test—involving methods of detecting and using cell-free fetal DNA— was invalid for lack of patent eligible subject matter. The decision adds to a long and growing list of patents that have fallen in the wake of the Supreme Court’s recent 35 U.S.C. § 101 jurisprudence. See Mayo Collaborative Servs. v. Prometheus Laboratories, Inc., 566 U.S. ___, 132 S. Ct. 1289 (2012); Ass’n for Molecular Pathology v. Myriad Genetics, Inc., 569 U.S. ___, 133 S. Ct. 2107 (2013); Alice Corp. v. CLS Bank Int’l, 573 U.S. ___, 134 S. Ct. 2347 (2014).

The claims at issue in Sequenom are directed to methods of amplifying and detecting the small fraction of paternally inherited cell-free fetal (cff) DNA from within cffDNA circulating in the maternal bloodstream. Maternal plasma and serum had been discarded as waste prior to the discovery of cffDNA in it. Sequenom commercialized the technology in the MaterniT21 test for evaluating fetal DNA, such as to determine paternity or diagnose fetal disorders. The non-invasive test was a significant improvement over the invasive, risky, and unreliable previous standards of care. Even the Court agreed that the patent was directed to “a significant human contribution … that revolutionized prenatal care.”

The Federal Circuit’s analysis of Sequenom’s patent relied on the two-step test articulated by the Supreme Court in Mayo for distinguishing between patent-ineligible claims to laws of nature, natural phenomena, and abstract ideas and patent-eligible applications of those categories. First, the court considers whether a claim is directed to a patent-ineligible concept. If it is, the court determines whether additional elements in the claim amount to an inventive concept sufficient to transform the claim into a patent-eligible application that amounts to significantly more than a patent on the ineligible concept itself.

The Court noted that the claims at issue begin with the natural phenomenon of cell-free fetal DNA in the bloodstream of pregnant women and end with the natural phenomenon of paternally inherited cffDNA. In the second analytical step, the Court analogized to Mayo and dismissed the additional cffDNA amplification and detection steps as “well-understood, conventional and routine” such that the claimed methods amount to no more than a “general instruction to doctors” to apply known techniques.

Sequenom highlights that even technologies which are game-changing in practice may not make for patent-eligible subject matter. In medical and biotechnological research and development, where use of “routine” laboratory techniques are the foundation of both ordinary and extraordinary discoveries, this decision makes uncertain what claim elements will be transformative enough to meet the § 101 threshold.

Applicants and practitioners should review the U.S. Patent and Trademark Office’s guidelines on subject matter eligibility here and both draft and prosecute applications with the guidelines as well as Sequenom and its predecessors in mind.