Pfizer Corp & Ors v Commissioner of Patents & Anor

Pfizer Corporation and others (the applicants) sought leave to appeal from a decision of the Full Federal Court of Australia concerning the patentability of a pharmaceutical substance. The Commissioner of Patents and another party (the respondents) were involved in the proceedings. The dispute centred on whether the applicants' invention, a pharmaceutical substance, was a "manner of manufacture" for the purposes of section 6 of the Statute of Monopolies, which is incorporated into Australian patent law.

The primary legal issue before the High Court was whether a claim for a pharmaceutical substance, which was not itself a "manner of manufacture" in the traditional sense of a chemical compound or a process, could nonetheless be patentable under Australian patent law. This involved considering the scope of the term "manner of manufacture" and its application to new pharmaceutical substances, particularly in light of the established principle that a mere discovery or scientific theory is not patentable.

The High Court, in a joint judgment, affirmed the decision of the Full Federal Court. Their Honours reasoned that the established understanding of "manner of manufacture" in Australian patent law, derived from English common law and applied in cases such as *National Research Development Corporation v Commissioner of Patents*, encompassed inventions that provided a practical, useful, and artificial contrivance or product. They held that a pharmaceutical substance, even if discovered, could constitute a manner of manufacture if it possessed a new and useful property or effect, thereby providing a practical application. The court distinguished between a mere discovery and an invention that offers a tangible benefit or solution to a problem, concluding that the applicants' claimed substance, with its identified therapeutic effect, fell within the latter category.

The High Court dismissed the application for leave to appeal.