On January 16, 2009, the Federal Court of Appeal issued its first decision interpreting and applying the obviousness test set out by the Supreme Court in Apotex Inc. v. Sanofi-Synthelabo Canada Inc. (Sanofi). The Court of Appeal’s decision confirms that, despite some differences of emphasis, Sanofi is consistent with the law of obviousness as it has developed in Canada over the last 25 years.  

The Effect of Sanofi  

In Apotex Inc. v. Pfizer Canada Inc., Apotex appealed an order prohibiting it from marketing generic sildenafil citrate (the active ingredient in Viagra®) until the expiry of Pfizer’s 446 patent. Apotex had alleged that the patent was invalid on the basis that it was obvious. The Federal Court rejected this allegation, stating that, at its highest, the invention was merely “worth a try” at the relevant time, which did not render it obvious.1  

In the Federal Court of Appeal, Apotex argued that whatever the result before Sanofi, the 446 patent could not survive the change to the law on obviousness. In particular, Apotex argued that the test from Sanofi harmonized the law of Canada with that of the United Kingdom, where courts have, in certain cases, found inventions obvious because they were merely worth a try. The Court of Appeal rejected Apotex’s arguments and dismissed the appeal. In so doing, the Court engaged in its first detailed consideration of the Supreme Court’s decision in Sanofi.  

The Federal Court of Appeal’s judgment recognized that Sanofi had adjusted the obviousness test. Before Sanofi, the idea that an invention might be “obvious to try” was never sufficient to render it obvious. However, the Supreme Court in Sanofi held that an obvious-to-try analysis might be appropriate in certain circumstances. The question before the Court of Appeal was therefore exactly how loose the Supreme Court had intended the test for obviousness to become. Was it enough that the invention might have been worth a try?  

Fortunately for innovators, the Federal Court of Appeal found that it was not. It specifically stated that “an invention is not made obvious because the prior art would have alerted the person skilled in the art to the possibility that something might be worth trying.” The Court of Appeal instead held that for an invention to be obvious it must have been “more or less self-evident” to a person of ordinary skill.  

Canadian Test for Obviousness Still Differs from U.K. Law

Apotex’s other major argument was that, since the U.K. courts had invalidated the equivalent patent, and (Apotex argued) the Supreme Court in Sanofi appeared to contemplate harmonizing the obviousness test with that used in the United States and the United Kingdom, the Federal Court of Appeal should find the 446 patent to be obvious. The Court rejected this approach, finding that in the United Kingdom, the key inquiry was whether a person skilled in the art had sufficient motivation to arrive at the invention, and that the expectation of success was a minor matter. The Court of Appeal held that this was not the law in Canada, concluding that “the degree of motivation cannot transform a possible solution into an obvious one.” For an invention to be obvious, it must be both obvious to try (not just “worthwhile to pursue”) and more or less self-evident, or “very plain” that it would work.  

A studied read of this important decision indicates that, in practical terms, Sanofi signals a modest evolution, rather than a radical transformation, in the law on obviousness. An invention will be obvious if it is more or less self-evident that the invention ought to work – and not simply that it ought to be tried.