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Claims to Detection and Analysis of Fetal DNA in Maternal Plasma Were Found Invalid for Failing to Transform the Subject Matter of the Claims From a Natural Phenomenon Into Patent-Eligible Subject Matter

Posted on Jun 22, 2015 in Blog

In Ariosa Diagnostics, Inc. v Sequenom, Inc. (No. 14-1139 (Fed. Cir. Jun. 12, 2015)) the United States Court of Appeals for the Federal Circuit (“CAFC”) upheld a decision by the U.S. District Court for the Northern District of California invalidating a patent covering a ground breaking technique for fetal testing and diagnostics.

The inventors discovered that fetal DNA was present in maternal plasma, and could be relatively easily tested for paternally derived nucleic acid sequences. Using this technique both the sex of the fetus, as well as testing for any possible fetal abnormalities, could be carried out using a relatively non-invasive maternal blood test, followed by, for example, PCR amplification of the fetal DNA present in the plasma sample. Before this discovery, genetic fetal testing required invasive techniques such as amniocentesis. The inventors were awarded U.S. Patent Number 6,258,540 (“ ‘540”). Generally, the claims of the ‘540 patent are directed to a method of detecting paternally inherited DNA of fetal origin in a maternal serum or plasma sample, which comprises amplifying the paternal inherited nucleic acid, and detecting the presence of the paternal inherited nucleic acid from the fetus in the sample plasma. (See Ariosa Diagnostics, Inc. v Sequenom, Inc., slip op. at page 3).

This invention was commercialized by Sequenom, Inc. as the MaterniT21® test. The case arose as a declaratory judgment action filed by Ariosa Diagnostics, Inc. in response to letters threatening claims of infringement sent by Sequenom.

The District Court agreed with Ariosa’s arguments that the claims of the ‘540 patent were invalid as being directed to natural phenomenon.

On appeal, the CAFC upheld the District Court’s finding. The CAFC applied the test set forth by the Supreme Court in its Mayo decision (Mayo Collaborative Services v. Prometheus Laboratories, Inc., 566 U.S. ___, 132 S. Ct. 1289 (2012)). The Mayo test comprises two steps: i) determine whether the claims at issue are directed to a patent ineligible concept, if yes, then ii) consider the elements of each claim both individually and “as an ordered combination” to determine whether additional elements “transform the nature of the claim” into a patent-eligible application. (Id. at 1298).

With regard to the first step, the CAFC found that the ‘540 claims were generally directed to detecting the presence of a naturally occurring thing or a natural phenomenon, i.e., fetal nucleic acid in maternal plasma or serum. The Court noted that the claimed method begins and ends with a naturally occurring phenomenon. (See Ariosa v Sequenom, slip op. at page 10).

Turning to the second prong of the Mayo test, the Court found that the ‘540 claims were merely a general instruction to doctors to apply routine, conventional techniques when seeking to detect the fetal DNA in the maternal plasma samples. According to the Court, because the method steps were well-understood, conventional and routine, the method of detecting paternally inherited fetal DNA is not new and useful. The Court set forth that the only subject matter new and useful as of the date of the application was the discovery of the presence of fetal DNA in maternal plasma or serum. (See Ariosa v Sequenom, slip op. at page 11).

The Court stated (Ariosa v Sequenom, slip op. at page at page 13):

Thus, in this case, appending routine, conventional steps to a natural phenomenon, specified at a high level of generality, is not enough to supply an inventive concept. Where claims of a method patent are directed to an application that starts and ends with a naturally occurring phenomenon, the patent fails to disclose patent eligible subject matter if the methods themselves are conventional, routine and well understood applications in the art. The claims of the ’540 patent at issue in this appeal are not directed to patent eligible subject matter and are, therefore, invalid.

The Court also generally addressed the issue of preemption. The Supreme Court’s Alice decision made it clear that the principle of preemption is the basis for the judicial exceptions to patentability. As the CAFC stated in this decision, patent claims should not prevent the use of the basic building blocks of technology – abstract ideas, naturally occurring phenomenon, and natural laws. According to the Court, while preemption may signal patent ineligible subject matter, the absence of complete preemption does not demonstrate patent eligibility. (See Ariosa v Sequenom, slip op. at page 14). However, the Court stated that where patent claims are deemed only to disclose patent ineligible subject matter under the Mayo framework, preemption concerns are fully dressed and made moot. (See Ariosa v Sequenom, slip op. at pages 14-15).


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