“More or Less Self-evident” Remains the Standard in the Obvious-to-Try Test

“More or Less Self-evident” Remains the Standard in the Obvious-to-Try Test

Eli Lilly Canada Inc v Mylan Pharmaceuticals ULC, 2015 FCA 286

An attack on the Federal Court’s (“FC”) slight rewording of the obvious-to-try test has proven unsuccessful.

Background: FC Finds Invention Obvious-to-Try

Eli Lilly brought an application under the Patented Medicines (Notice of Compliance) Regulations, to prohibit Mylan Pharmaceuticals ULC from being issued a Notice of Compliance for a generic version of the drug tadalafil until after the expiration of Canadian Patent No. 2,379,948 (the “’984 Patent”). [1]

In response, Mylan claimed that it would not infringe the ‘948 Patent and that the ‘948 Patent was invalid on the basis that it was obvious. The FC agreed with Mylan and held that the allegations of non-infringement and invalidity were justified, employing the obvious-to-try test. Eli Lilly appealed the FC decision, alleging legal and factual errors on the part of the Judge. [2]

Minor Rephrasing of “Obvious-to-Try” Test Not Material

Eli Lilly alleged that the FC Judge erred in law in his obviousness analysis by asking the incorrect question at the first step in the obvious-to-try test. [4] Eli Lilly cited paragraph 150 of the FC reasons, where the Judge wrote that the “test, rather, is whether the skilled person had good reason to pursue predictable solutions or solutions that provide a ‘fair expectation of success.'” [4]

The proper test, as set out by the Supreme Court of Canada in Apotex v Sanofi-Synthelabo Canada Inc, (2008 SCC 61), differs slightly: “For a finding that an invention was ‘obvious to try’, there must be evidence to convince a judge on a balance of probabilities that it was more or less self-evident to try to obtain the invention. Mere possibility that something might turn up is not enough.” [66]

The FCA held that any conceivable error by the FC Judge in the way he initially articulated the test for assessing obviousness was not salient to the FC decision. [5] The FCA upheld the finding of invalidity and non-infringement and dismissed the appeal with costs.


Despite its slight rephrasing of the obvious-to-try test, the FC Judge’s conclusion that the ‘948 Patent was obvious to try was in line with the test used in Sanofi. It is not surprising that the FC Judge was not held to the strict wording of the Sanofi decision, considering the Supreme Court’s own departure in Sanofi from the restrictive obviousness tests of the past, and its own characterization of the obvious-to-try test as a non-exhaustive set of factors to be taken into consideration in accordance with the evidence in each case (Sanofi at paras 60, 69).