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21 July 2016AmericasStephen Stout and Rachael McClure

Ariosa v Sequenom: keeping the Mayo test in place

On June 27, the US Supreme Court denied a request to revisit the question of patent eligibility for inventions that apply known techniques to newly discovered natural phenomena in Sequenom  v. Ariosa Diagnostics. In light of the denial, the high court’s test for patent eligibility will remain unaltered from its 2012 decision in Mayo v Prometheus. The decision to deny certiorari leaves the patent eligibilty of many life sciences-related patent claims, and in particular, those directed to diagnostic tools, in jeopardy, even if they “combine[] and utilize[] man-made tools of biotechnology in a new way that revolutionize[s]” the field (Ariosa).

The patent at issue in Ariosa, US patent number 6,258,540 (’540 patent), resulted from the discovery of foetal DNA in maternal blood samples, termed cell-free foetal DNA (cffDNA). That discovery led to the development of a non-invasive prenatal test that required only a maternal blood sample, an alternative to the then standard, but invasive, prenatal tests such as amniocentesis.

The claims in the ’540 patent relate to that non-invasive testing, specifically to methods for amplifying and detecting cffDNA in a maternal blood sample. While the laboratory techniques that could be used in the claimed methods were well known at the time of the invention, for example, polymerase chain reaction (PCR) and gel electrophoresis, cffDNA was first discovered and first subject to these methods of analysis by the named inventors of the ’540 patent.

When Sequenom filed its petition for certiorari, the claims in the ’540 patent stood invalid as patent-ineligible. Under the Mayo framework, courts resolve patent eligibility by first determining whether the claims relate to a natural law or natural phenomenon, and if so, then determining whether the other elements of the claim “transform the nature of the claim” into a patent-eligible application of the law or phenomenon. Mayo also stated that “[p]urely conventional or obvious pre-solution activity is normally not sufficient to transform an unpatentable law of nature into a patent-eligible application of such a law.”

Applying that framework, the US District Court for the Northern District of California had granted summary judgment of invalidity, finding that the ’540 patent claims were not directed to patent-eligible subject matter. Specifically, the district court determined that the claimed method was patent-ineligible because “the only inventive component of the processes of the ’540 patent is to apply those well-understood, routine processes to paternally inherited cffDNA, a natural phenomenon.”

On appeal, a US Court of Appeals for the Federal Circuit panel agreed that, following Mayo, the DNA amplification and detection techniques recited in the claims of the ’540 patent were not sufficiently innovative to transform naturally-occurring cffDNA into a patent-eligible invention.

“The US District Court for the Northern District of California had granted summary judgment of invalidity, finding that the ’540 patent claims were not directed to patent-eligible subject matter.”

A number of judges at the Federal Circuit expressed concern, however, about the outcome dictated by Mayo. In a concurring opinion to the panel decision, Judge Linn observed that “[b]ut for the sweeping language in the Supreme Court’s Mayo opinion, [he] see[s] no reason, in policy or statute, why Sequenom’s breakthrough invention should be deemed patent ineligible.”

Later, in opinions concurring with the denial of Sequenom’s petition for rehearing en banc, Judge Lourie (with Judge Moore joining) and Judge Dyk separately echoed Linn’s concerns regarding the restrictive nature and broad scope of the Mayo rule. Lourie’s opinion described Sequenom’s patent as “an important discovery and a valuable contribution to the medical field” and reasoned that the asserted claims “should not be patent-ineligible on the ground that they set forth natural laws or are abstractions” because “before this invention, the amplification and detection of cffDNA from maternal blood, and use of these methods for prenatal diagnoses, were not routine and conventional.”

Nonetheless, Lourie agreed that the courts are bound by Mayo’s broad precedent. In a similar vein, Dyk criticised Mayo for “not fully tak[ing] into account the fact that an inventive concept can come not just from creative, unconventional application of a natural law, but also from the creativity and novelty of the discovery of the law itself.” Dyk noted that “[t]his is especially true in the life sciences, where development of useful new diagnostic and therapeutic methods is driven by investigation of complex biological systems.”

Amicus briefs

Reflecting the concerns expressed at the Federal Circuit, no fewer than 22 amicus briefs were filed in support of Sequenom’s petition for certiorari. The amici included top industry players, biotechnology groups, bar associations, and academics. The briefs urged the Supreme Court to grant the petition for a variety of reasons, including: (i) policy-based arguments related to promoting innovation and economic investment in biotechnology/diagnostics; (ii) criticisms of the Mayo framework (or the panel’s application of it) for not considering the inventive nature of Sequenom’s claim “as a whole”; (iii) criticisms of the Federal Circuit for failing to conduct a “preemption” analysis, ie, to consider whether Sequenom’s claims preempt other/future uses of cffDNA; (iv) opinions on the need for international harmonisation of patent eligibility principles; and (v) academic analyses of whether there is an “inventive concept/application” hurdle for patent eligibility at all.

An overarching theme of the briefs was that Mayo is being applied too broadly in the realm of diagnostic inventions, where nearly every tool relies in some way on a naturally-occurring substance in the body.

Despite the clamour from all corners for more guidance on the scope and application of the Mayo test, the Supreme Court denied Sequenom’s petition. The two-part Mayo test will, therefore, remain in place for the foreseeable future. And it will continue to raise questions over the patent eligibility of life sciences-related inventions, particularly for claims related to diagnostic tools and other natural phenomena.

This article is intended for educational and informational purposes only and does not constitute legal advice or services. These materials represent the views of and summaries by the author. They do not necessarily reflect the opinions or views of Vinson & Elkins or of any of its other attorneys or clients.

Stephen Stout, PhD, is a partner at  Vinson & Elkins in Austin. He can be contacted at:

Rachael McClure is an associate at Vinson & Elkins in New York. She can be contacted at:

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