Praxair v. Mallinckrodt: An Expanded Interpretation of the Printed Matter Doctrine with Important Implications for Biotechnology

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Although the “printed matter doctrine” has a long history in U.S. patent law, until recently it has played a relatively minor role in policing patent-ability, so much so that an article published in 1994 essentially wrote it off as nothing more than an “archaic common law has-been.” Although the doctrine is rooted in the concept of patent eligibility, it is never mentioned in recent patent eligibility decisions of the U.S. Supreme Court such as Mayo and Alice, and patent law treatises and casebooks tend to give the doctrine little if any coverage. At its core, the printed matter doctrine has traditionally functioned to prevent the patenting of a product in situations where the sole purported basis for patent-ability resides in novel and non-obvious information appended to a product that is otherwise unpatentable in view of the prior art. Historically, the doctrine has been invoked with respect to physical products paired with literally printed material, i.e., printed information on a physical substrate such as paper or a computer-readable medium. Recent judicial decisions have, however, expanded the doctrine to encompass method claims, as well as information that is not embodied in any physical medium, such as advice orally provided by a physician to a patient. In the Federal Circuit’s most recent printed matter case, Praxair v. Mallinckrodt, decided in May 2018, the court expanded the doctrine still further, holding that a limitation in a method claim reciting a step of merely thinking about information, i.e., a mental step, constitutes printed matter. The printed matter doctrine is increasingly being applied in the life sciences, particularly with respect to new methods of using known drugs for known indications.

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Biotechnology Law Report