The 'Reasonably Diligent Search' In Canadian Obviousness Analysis

Overview

Can a book on a dark and dusty shelf in a public library render a patent obvious? In the recent decision of E Mishan & Sons Inc v Supertek Canada Inc, 2015 FCA 163, the Federal Court of Appeal noted that none of the parties made any submissions regarding whether the codification of the test for obviousness changed the test for determining what documents would be included as part of the relevant prior art. Absent any such submissions, the Court of Appeal applied the "reasonably diligent search" test.

Background

Prior to the 1996 amendments to the Patent Act there was no explicit requirement of non-obviousness in the Patent Act. Instead, the concept of non-obviousness was implicit in the definition of invention under section 2. In defining the requirement, the courts established that, to be citable for the purposes of obviousness, the reference had to be findable through a "reasonably diligent search".

Non-obviousness is now explicitly codified in section 28.3 of the Patent Act. This section states that prior art must be "available to the public" to be citable. In the leading case on obviousness in Canada, Apotex Inc v...