Patentable Subject Matter

CIPO has published practice guidance on patentable subject matter following the recent decision in Choueifaty as well as some examples for computer-implemented, medical diagnostic and medical use inventions. CIPO indicated that updates to MOPOP are coming later and will be subject to consultation.

The practice guidance (link) discusses applying ‘purposive construction’ to the determination of patentable subject matter. See my co-authored article on the Choueifaty decision. From the practice guidance (emphasis added/footnotes omitted):

The goal of purposive construction of a claim is to determine the fences of the monopoly claimed by the applicant.

To be both patentable subject-matter and not be prohibited under subsection 27(8) of the Patent Act, the subject-matter defined by a claim must be limited to or narrower than an actual invention that either has physical existence or manifests a discernible physical effect or change and that relates to the manual or productive arts, meaning those arts involving or concerned with applied and industrial sciences as distinguished in particular from the fine arts or works of art that are inventive only in an artistic or aesthetic sense.

An element may thus be an essential element of the claim because the applicant intended it to be essential even though it has no material effect on the working of the invention. Such an element would not form part of the actual invention because the fact that it has no material effect on the working of the invention means it does not cooperate with other elements of the claimed invention.

The mere fact that a computer is identified to be an essential element of a claimed invention for the purpose of determining the fences of the monopoly under purposive construction does not necessarily mean that the subject-matter defined by the claim is patentable subject-matter and outside of the prohibition under subsection 27(8) of the Patent Act. In such a case, it is necessary to consider whether the computer cooperates together with other elements of the claimed invention and thus is part of a single actual invention and, if so, whether that actual invention has physical existence or manifests a discernible physical effect or change and relates to the manual or productive arts.