SUPREME COURT OF CANADA WEIGHS IN ON PATENTABILITY OF METHODS OF MEDICAL TREATMENT
By Joanne Chriqui, Scott MacKendrick, Fortunat Nadima, Catherine Thall Dubé and Mathilde Trottier
ROBIC
LAWYERS, PATENT AND TRADEMARK AGENTS
On July 17, 2026, the Supreme Court of Canada answered the question of whether methods of medical treatment are patentable in Canada.[1] Methods of medical treatment, per se, are not patentable. The Court’s finding maintains more than a half-century of “unbroken” Canadian case law, and it is grounded in the broad principle that professional skills are not the proper subject matter for a patent.
Context
Central to this question before the Court in Pharmascience Inc. v. Janssen Inc. was Canadian Patent No. 2,655,335 (the “335 Patent”), which claims a dosing regimen for the drug INVEGA SUSTENNA, a long-acting injectable formulation of paliperidone palmitate for the treatment of schizophrenia (the dosing regimen teaches the timing of two loading doses, followed by monthly maintenance doses). The question arose from an infringement action brought by Janssen under the Patented Medicines (Notice of Compliance) Regulations (“PM(NOC) Regulations”).
One of the issues before the Federal Court and the Federal Court of Appeal was whether the 335 Patent is invalid for claiming unpatentable subject matter. Both courts did not find it invalid on that basis.
On appeal to the Supreme Court against the Federal Court of Appeal decision, the Court considered:
- whether methods of medical treatment constitute patentable subject matter under Canadian law
- how such methods should be defined
- whether, and in what circumstances, should drug dosing regimens be considered as amounting to methods of medical treatment
Are MMTs patentable?
The Patent Act is a creature of statute, and the Patent Act contains no express prohibition against MMT claims. So, if MMTs are not patentable subject matter, then where is that prohibition found?
The Supreme Court’s 1972 Tennessee Eastman[2]decision is Canada’s historical origin for the prohibition on MMT patentability. At the time of the decision, the Act included section 41(1), which prohibited the patenting of a substance intended for food or medicine except when prepared or produced by particular methods or processes of manufacture. The section was repealed in 1987, however, and no prohibition on the patenting of MMTs was added to the Act.
In a series of Federal Court, Federal Court of Appeal and Supreme Court of Canada decisions that issued after the Tennessee Eastman decision, including after the repeal of section 41(1), the Honourable Justice Jamal, writing for the majority[3], observed that no court at any level had ruled against the unpatentability of MMTs (and, more broadly, he noted that the Supreme Court had affirmed that professional skills are not patentable). After observing that the definition of “invention” in section 2 of the Act had been “largely unchanged since 1869” and that it “signalled” an intention to exclude certain subject matter, he found comfort in the historical consistency of the approach to the patentability of MMTs. He observed that the patentability interpretation should be “attentive to the wisdom of the case law” and that it was “settled law” in Canada that MMTs are not patentable subject matter.
Returning to Justice Jamal’s note that the Supreme Court had affirmed post-Tennessee Eastman that professional skills are not patentable, this observation about the failure of professional skills to satisfy the patent bargain is at the centre of the Supreme Court’s decision:
“Allowing professional skills to be patentable would not advance the purpose of the Patent Act, which is to stimulate innovation. Professionals are already under ethical obligations to exercise their skills in their clients’ best interests and to share those skills widely. They neither need nor should they receive patent protection to do so. Because professional skills do not respond to the incentives of the patent bargain, patenting them is unjustified.”
Justice Jamal concluded that any change to “consistent” MMT patentability law would “unsettle more than a half-century of commercial expectations”, and if change is to occur, “it must come from Parliament, not this Court”.
How should (unpatentable) MMTs be defined?
Justice Jamal favoured the adoption of a “balanced approach” to the test for methods of medical treatment. The test should distinguish between the exercise of professional skill and judgment, which need not be incentivized by the patent bargain, and other medical innovations, thereby ensuring that commercial innovation within the field of medical practice is not stifled. The “ultimate question” is whether that subject matter amounts to professional medical skill and judgment. If a claimed invention seeks to “fence in” an area of medical treatment it is vulnerable to being found impermissible. The approach:
- construe the claims to determine the subject matter
- analyze “the real subject matter of the claim” for methods of medical treatment, regardless of how the claim is drafted
- for instance, a product claim is not necessarily a vendible product (or non-MMT) claim, and
- a vendible product claim may include a dosage regimen as an essential element
- applying the test for methods of medical treatment to the subject matter of the claim, once it has been properly construed, is a “factually suffused” issue that “depends on the evidence”, with the considerations including
- analysis should focus on whether the subject matter amounts to professional medical skill and judgment, not whether professional medical skill and judgment would be applied in selecting the claimed invention for a particular patient or use;
- the more the practice of a claimed invention involves tailoring it to the circumstances of a particular patient, the more likely it is that its subject matter amounts to professional medical skill and judgment; and
- the test must remain focused on the purpose of the rule that methods of medical treatment are unpatentable subject matter; the more a medical professional would already be incentivized to develop or improve a given subject matter in the course of their professional practice, the more likely it is that the subject matter amounts to a method of medical treatment.
Should drug dosing regimens be considered as amounting to MMT?
The patentability of a dosing regimen is a “factually suffused” exercise that depends on how the dosing regimen is intended to be, or has been, applied. There is no “categorical distinction” between fixed and variable dosages; it is at best a sometimes useful “evidentiary proxy”. And if a minority of physicians wish to “deviate” from the dosing regimen, this does not necessarily render a dosing regimen unpatentable.
Conclusions
Methods of medical treatment continue to be unpatentable subject matter in Canada. Dosing regimens are not, however, necessarily unpatentable. The analysis of what is and is not patentable is a factually suffused exercise, and, accordingly, we anticipate that more litigation on what is and is not patentable will inevitably continue.
[1] Pharmascience Inc. v. Janssen Inc., 2026 SCC 26.
[2] Tennessee Eastman Co et al. v Commissioner of Patents, [1974] SCR 111, 1972 CanLII 167 (SCC)
[3] The concurring reasons reached the same disposition as that of the majority, but differed in respect of the issue of whether MMTs are, per se, unpatentable.
