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The Death Of The Genus Claim, Dmitry Karshtedt, Mark A. Lemley, Sean B. Seymore

GW Law Faculty Publications & Other Works

The central feature of patent law in the chemical, biotechnology, and pharmaceutical industries is the genus claim – a patent that covers not just one specific chemical but a group of related chemicals. Genus claims are everywhere, and any patent lawyer will tell you they are critical to effective patent protection.

But as we show in this article, the law has changed dramatically in the last twenty-five years, to the point where it is no longer possible to have a valid genus claim. Courts almost always hold them invalid. Remarkably, they do this without having acknowledged that they have fundamentally …