Enforcing diagnostic method patents in a world of patchwork protection – Landslide

Leah McGurn

Jan 11, 2023

Securing effective patent protection over inventive diagnostic methods continues to be a challenge in several jurisdictions around the world, particularly in the U.S. It will be important to follow unfolding legal developments for a better sense of which diagnostic methods are U.S. patent-eligible, suggests Vincent M. de Grandpré and Leah McGurn in their article published in Landslide by the American Bar Association.

Parallel U.S. and foreign cases illustrate how the validity and enforceability of diagnostic method patents in any jurisdiction may have implications around the world. For example, in the late 1990s, Sequenom, a company specializing in molecular diagnostics, developed a method for detecting fetal DNA in a maternal blood sample. The company filed international patent applications. In the U.S., the Federal Court held that the patent claims were “directed to” a natural phenomenon and that there was no inventive concept sufficient to transform the nature of the claim into a patent-eligible application. As a result, Sequenom’s patent claims were ruled invalid.

Under U.K. law, whether a diagnostic method is patentable subject matter turns on whether, as a matter of substance and not mere form, a claimed invention is a practical product or process rather than information about the natural. The U.K. court held that Sequenom’s patent was directed to patentable subject matter. The claims were not directed to information about the natural world, but rather to a detection method that did not exist in the natural world. Although Sequenom’s patent rights have not been litigated in Canada, a Canadian court might well look at the issues in a manner more similar to the U.K. rather than the U.S. approach.

If you have a subscription to Landslide, you can read the full article published by the American Bar Association on January 11, 2023.