The Federal Circuit has issued its long-awaited decision in Ariosa Diagnostics, Inc. v. Sequenom, Inc., but the decision is not good news for those seeking to obtain or enforce U.S. patents on diagnostic methods. The appeals court affirmed the district court’s finding that Sequenom’s claims are invalid under 35 USC § 101, applying the analytical framework set forth in the U.S. Supreme Court’s Mayo decision in a way that could have a ripple effect across the diagnostic and personalized medicine industry.

The Claims At Issue 

The Sequenom patent at issue was U.S. Patent 6,258,540. The claimed technology relates to diagnostic methods for determining certain fetal characteristics such as gender and genetic defects, based on paternally inherited cell-free fetal DNA (cffDNA) found in maternal plasma and serum. The independent claims at issue in this appeal are set forth below.

1. A method for detecting a paternally inherited nucleic acid of fetal origin performed on a maternal serum or plasma sample from a pregnant female, which method comprises amplifying a paternally inherited nucleic acid from the serum or plasma sample and detecting the presence of a paternally inherited nucleic acid of fetal origin in the sample.

24. A method for detecting a paternally inherited nucleic acid on a maternal blood sample, which method comprises: removing all or substantially all nucleated and a nucleated cell populations from the blood sample, amplifying a paternally inherited nucleic acid from the remaining fluid and subjecting the amplified nucleic acid to a test for the paternally [sic] inherited fetal nucleic acid.

25. A method for performing a prenatal diagnosis on a maternal blood sample, which method comprises obtaining a non-cellular fraction of the blood sample amplifying a paternally inherited nucleic acid from the non-cellular fraction and performing nucleic acid analysis on the amplified nucleic acid to detect paternally inherited fetal nucleic acid.

The Patent Eligibility Problem

The Federal Circuit decision was authored by Judge Reyna and joined by Judges Linn and Wallach. Judge Linn also filed a concurring opinion.

The court applied Mayo’s two-step framework for determining patent eligibility, considering first whether the claims are directed to a patent-ineligible concept, and, if they are, determining whether the additional claim elements “transform the nature of the claim” into a patent-eligible application of the natural phenomenon.

With regard to the first step, the court noted that the claims start and end with naturally occurring material (cffDNA). Thus, the court found them to be caught by the first step of the two-step Mayo framework, and require analysis under the second step.

With regard to the second step, the court considered whether the process steps recite additional features that are new and useful. However, instead of considering the process steps as a whole, and recognizing that amplifying a paternally inherited nucleic acid from a serum sample from a pregnant female was new, and that detecting the presence of a paternally inherited nucleic acid of fetal origin in the sample was new and useful, the court found that the method steps did not support patent eligibility because they used conventional amplification and detection techniques. The court separately considered several dependent claims, but found none to add anything “inventive” to the claimed methods.

The court’s conclusion indicates how it may analyze other diagnostic method claims for patent eligibility:

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.

 Judge Linn’s Concurrence

Judge Linn’s concurring opinion places blame for the result here squarely on the shoulders of the Supreme Court and its decision in Mayo. Judge Linn urges the Court to reconsider the Mayo framework, and at least permit the consideration of “post-solution activity” when that activity is novel.

A Ripple Effect Across The Diagnostic Industry 

While the contours of this decision have yet to be determined, it at least appears to leave room for patent eligibility where method claims recite novel laboratory techniques or reagents. However, it may make it more difficult to obtain patents related to diagnostic methods, personalized medicine, and other method claims that involve a “natural phenomenon.” Even if the Supreme Court grants certiorari, it will be another year before we could have a different decision. While various groups are working on possible legislative solutions to the patent eligibility problem, it will take time to negotiate statutory language that is agreeable to all stakeholders, and even longer for any proposed legislation to make is way through Congress.


To make sure you do not miss out on regular updates from the Kluwer Patent Blog, please subscribe here.

Kluwer IP Law

The 2022 Future Ready Lawyer survey showed that 79% of lawyers think that the importance of legal technology will increase for next year. With Kluwer IP Law you can navigate the increasingly global practice of IP law with specialized, local and cross-border information and tools from every preferred location. Are you, as an IP professional, ready for the future?

Learn how Kluwer IP Law can support you.

Kluwer IP Law
This page as PDF