Prohibiting Medical Method Patents: A Criticism of the Status Quo

Methods of medical treatment are not patentable in Canada. This means that inventions involving the performance of surgery, administration of medicine, or extraction of fluids or tissue for diagnostic tests cannot directly be protected under the current patent regime. However, this prohibition is not an absolute ban. Many medical innovations are patentable, including surgical tools and devices, drugs and other chemical compounds, medical “uses”, diagnostic assays and methods of treat- ing “natural” conditions. The practical reality is that the distinction between what is and what is not patentable is poorly defined. This uncertainty presents a steep challenge for inventors and patent agents in preparing patent claims that appropriately encapsulate a particular medical invention without claiming prohibited subject matter. This confusion also hinders the public and would-be inventors wishing to navigate the patent landscape. Part I of this paper entitled “Legal Basis for the Prohibition” summarizes the statutory and jurisprudential basis for prohibiting medical method patents. Part II entitled “Patentability of Medical Methods in Practice” discusses how this prohibition has been applied by courts and the Commissioner of Patents. Inconsistencies in its application are highlighted and practical guidance is provided on how to protect aspects of medical inventions without triggering the prohibition. Part III entitled “Criticism of the Status Quo” argues that the rationale for prohibiting medical method patents is tenuous, based more on public policy than the Patent Act. Based on the irregular application of the prohibition revealed in Part II and the criticisms raised in Part III, legislative reform is recommended