In a blog entitled The Patent Policy That Could Harm Canada’s Patients, Laura Crist of the Global Intellectual Property Center, U.S. Chamber of Commerce, condemned Canada’s patent case law for requiring Canadian patents to achieve the promise set out in the patent specification. Although it is true that many patents, particularly in the pharmaceutical field, have been found invalid on this basis, it is also true that many pharmaceutical patents have been found valid and infringed, a point Crist conveniently ignores.
Canada has been on and off the United States Trade Representative IP “watch list” for years as not sufficiently respecting intellectual property rights of U.S. entities. However, the U.S. is hardly a paragon of virtue when it comes to respecting intellectual property rights of foreigners. For many generations before the U.S. became a net exporter of works protected by IPR, it was a pirate nation when it came to certain aspects of intellectual property protection. In 1891, U.S. copyright law for the first time granted U.S. copyright to non-U.S. authors, but there was a catch: The books of foreign authors had to be manufactured in the U.S. By the end of the Second World War, the U.S. became a net exporter of books, and it was not until then that the U.S. shifted its policy from protecting its domestic publishers to cautiously embracing global treaties. It took the U.S. until 1988 to adhere to the Berne Convention for the Protection of Literary and Artistic Works. Canada adhered to Berne 60 years earlier.
With respect to patents, U.S. patent law discriminated against foreign inventors for many decades. In interference proceedings, many foreign inventors had to prove that their inventions were reduced to practise in the U.S., which put them at a serious disadvantage relative to U.S. inventors.
With this background, here’s a brief summary of Canadian law with respect to the promise doctrine.
An invention must be useful to be patentable under Canadian law. If the patent specification does not promise a specific result, only a “scintilla of utility” is required. However, where the specification promises a specific result, utility will be measured against that promise, based on what is disclosed in the patent specification at the filing date. This is particularly relevant in the case of pharmaceutical inventions, because the requirement of utility means that the drug for which a patent is sought must achieve the result promised in the specification.
The “promise doctrine” is not new. It is rooted in a 1981 decision of the Supreme Court of Canada, Consolboard Inc v. MacMillan Bloedel (Sask) Ltd, in which the Court defined patent inutility as meaning “that the invention will not work, either in the sense that it will not operate at all or, more broadly, that it will not do what the specification promises that it will do.”
Canadian courts continue to cite Consolboard for the definition of utility in Canadian patent law. Although the term “promise” was first introduced in Consolboard, Canadian courts have long recognized the principle of holding patentees to their assertions of utility.
Holding patentees to their promises of utility serves important policy objectives. Requiring that statements of an invention’s utility are true or soundly predicted to be true assures that patents reward innovation and are not granted based on mere speculation or guesswork. If that were otherwise, monopoly rights resulting from mere speculation could be enforced to prohibit others from pursuing promising lines of research or innovation. Canada’s utility requirements also safeguard against patentees overstating the usefulness of their inventions and assure that the public receives the benefits bargained for in exchange for the patentee’s monopoly rights.
Crist has criticized Canadian “promise” case law for invalidating pharmaceutical patents for lack of utility despite the fact that the medicines at issue were commercially successful. That argument overlooks the fact that utility cannot be based on mere speculation even if it turns out to be successful. For patents that rely upon sound prediction, the utility analysis asks whether the patent specification as filed supports the inventor’s prediction, not whether the invention ultimately achieves commercial success. The real controversy around the “promise doctrine” is how the courts are assessing what, if any, promises are given in the specification. In some of the cases that have led to invalidity, the courts have taken statements from an applicant’s own disclosure to make inferences about a heightened level of utility. In other cases, the courts have found that the statements in the disclosure are mere goals or objectives and not promises. It is against this construed level of utility that the question of sound prediction is then determined.
Patents for drugs such as Eli Lilly’s Zyprexa (olanzapine) or Pfizer’s Xalatan (latanoprost) were invalidated in Canada for failing to uphold their end of the patent bargain despite their subsequent commercial success. Both patents were construed by the courts to claim medicines to treat chronic conditions, schizophrenia and glaucoma, respectively, having improved therapeutic success and fewer side effects than the state of the art. As is common in the pharmaceutical industry, both patents relied upon the doctrine of sound prediction to establish utility. Both patents disclosed data demonstrating efficacy in the short term; yet neither disclosed experimental evidence to support the construed promises of improved efficacy and reduced side effects in the long-term treatment of these chronic conditions. Consequently, the courts found that Lilly and Pfizer had not soundly predicted the construed utility when they filed their patent applications.
Following invalidation of Eli Lilly’s patents for the Zyprexa and Strattera drugs, Lilly launched a chapter 11 North American Free Trade Agreement challenge against the government of Canada. Lilly claimed that the promise doctrine fundamentally changed Canada’s utility requirement, exceeds patentability requirements of trading partners, contravenes Canada’s international trade obligations and discriminates against pharmaceutical patents.
On March 16, the tribunal unanimously dismissed Lilly’s claims, finding instead that Canada’s utility requirements are not discriminatory.
The tribunal found that enforcing voluntary statements of utility assures that the public receives its end of the patent bargain while also preventing overclaiming. Moreover, the specific disclosure requirements for patents where utility is based on sound prediction is the consideration an inventor pays for obtaining a patent without having proved actual utility as at the filing date of the patent application.
Canada’s patent utility requirements and the workability of the promise doctrine are currently before the Supreme Court of Canada in AstraZeneca Canada Inc v Apotex Inc, in litigation over the validity of Astrazeneca’s patent for the acid reflux medicine Nexium (esomeprazole). The court’s decision is pending and is hoped to give further authority to the scope of the utility requirement in Canada.