On June 30, 2017, the Supreme Court of Canada, released a landmark patent decision (2017 SCC 36) abolishing Canada's so-called 'Promise Doctrine' by finding it "unsound", "not good law" and "incongruent with the both the words and scheme of the Patent Act."

The sole issue on appeal was whether AstraZeneca's patent for its blockbuster NEXIUM drug was invalid for lack of utility under s. 2 of the Patent Act. The Supreme Court unanimously allowed AstraZeneca's appeal, overturning the lower court decisions, and in so doing did away with a controversial doctrine of Canadian law that has been criticized by academics, foreign governments and research-based pharmaceutical companies.

Canada's unique Promise Doctrine, as developed by the Federal Courts' jurisprudence, involves reviewing the patent as a whole to identify any "promises" and then assessing whether those promises are met in order to satisfy the utility requirement. As stated by the trial judge, "the promise of the patent is the yardstick against which utility is measured".

The trial judge found AstraZeneca's patent novel and non-obvious. However, the patent was found to lack utility under the Promise Doctrine. Although the patentee fulfilled one promise (use as a proton pump inhibitor to reduce acid in the stomach), a second promise had not been fulfilled (improved metabolic properties). The decision was upheld by the Federal Court of Appeal.

On appeal, the Supreme Court of Canada criticized the Promise Doctrine as "unsound" and having no basis in the Patent Act:

The effect of the Promise Doctrine to deprive such an invention of patent protection if even one "promised" use is not soundly predicted or demonstrated is punitive and has no basis in the Act. Furthermore, such a consequence is antagonistic to the bargain on which patent law is based wherein we ask inventors to give fulsome disclosure in exchange for a limited monopoly (British United Shoe Machinery Co. v. A. Fussell & Sons Ltd. (1908), 25 R.P.C. 631(C.A.), at p. 650). To invalidate a patent solely on the basis of an unintentional overstatement of even a single use will discourage a patentee from disclosing fully, whereas such disclosure is to the advantage of the public. The Promise Doctrine in its operation is inconsistent with the purpose of s. 27(3) of the Act which calls on an inventor to "fully describe the invention and its operation or use". Thus, the Promise Doctrine undermines a key part of the scheme of the Act; it is not good law [emphasis added].

The Supreme Court set out the correct two-step approach that Courts should take in assessing utility:

First, courts must identify the subject-matter of the invention as claimed in the patent. Second, courts must ask whether that subject-matter is useful — is it capable of a practical purpose (i.e. an actual result)?

As to the "degree or quantum of usefulness" required, the Supreme Court reaffirmed that "a scintilla of utility will do." The Court also held that a single use related to the nature of the claimed subject-matter is sufficient and that utility can be established by either demonstration or sound prediction as of the filing date. The Supreme Court rationalized that such a standard served the purpose of the utility requirement under the Patent Act:

The utility requirement serves a clear purpose. To avoid granting patents prematurely, and thereby limiting potentially useful research and development by others, the case law has imposed a requirement that an invention's usefulness be demonstrated or soundly predicted at the time of application, rather than at some later point. This ensures patents are not granted where the use of the invention is speculative. What matters is that an invention "be useful, in the sense that it carries out some useful known objective" and is not merely a "laboratory curiosity whose only possible claim to utility is as a starting material for further research" (Re Application of Abitibi Co. (1982), 62 C.P.R. (2d) 81, (Patent Appeal Board and Commissioner of Patents), at p. 91).

Future Courts are directed to interpret section 2 in line with its purpose, which the Supreme Court explained is "to prevent the patenting of fanciful, speculative or inoperable inventions."

For patent applicants and patent owners, this case confirms that the statutory requirements for inventions and disclosures in the Patent Act provide the touchstones for patentability in Canada. Per subsection 27(1), the Patent Office must grant a patent if the "requirements for the issuance of a patent under this Act are met". The so-called Promise Doctrine and other extra-statutory bases for denying patents are improper grounds for rejection during prosecution of a patent application in Canada.

In conclusion, this decision marks an important course correction for Canadian courts in the assessment of patent utility and significantly lowers the bar for a patentee to defend against a utility challenge. It is a decision that many will say is long overdue but entirely welcome.

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