Tuesday, February 18, 2020

The State of the Art Includes All Prior Art

Hospira Healthcare Corporation v. Kennedy Trust for Rheumatology Research 2020 FCA 30 Locke JA: Rivoalen, Nadon JJA var’g 2018 FC 259 Phelan J
            2,261,630 / infliximab / INFLECTRA

The third step of the Windsurfing/ Pozzoli approach to obviousness, as approved by the Supreme Court in Sanofi 2008 SCC 61 [67], requires the court to “[i]dentify what, if any, differences exist between the matter cited as forming part of the ‘state of the art’ and the inventive concept of the claim or the claim as construed.” But what is the “state of the art”? The FCA in this case has clarified a point which has been obscure since codification of the non-obviousness requirement a quarter of a century ago.

The requirement that a patentable invention must involve an inventive step first emerged in the English case law in the late nineteenth century. Originally conceived of as an aspect of novelty, it soon because recognized as a distinct requirement, often referred to as requiring proper “subject-matter.” The current requirement that the invention be non-obvious to a person of ordinary skill in the art originated as a test for inventiveness on the particular facts of the case, propounded by Sir Sanford Cripps as counsel in Sharp & Dohme v Boots Pure Drug Co (1928), 45 RPC 153 (CA) at 162-63 and adopted by Lord Hanworth MR at 173. So conceived, the obviousness inquiry was taken to be an essentially factual inquiry as to whether the invention would have been obvious to a person skilled in the relevant art. From this it follows directly that the state of the art does not comprise the entire body of publicly available information, but is restricted to that information which would actually be available to the skilled person. So, in General Tire [1972] RPC 457, 497-98, the English Court of Appeal considered the state of the art to include only that material that would be available to a skilled person after a reasonably diligent search.

This was well settled law prior to codification. A question then arose on codification because s 28.3 of the Act provides that obviousness is to be assessed in light of information disclosed “in such a manner that the information became available to the public in Canada or elsewhere.” On its face this states that the entire body of public information constitutes the state of the art. The operative wording is exactly the same as that in the novelty provision (though the novelty provision, in a separate paragraph, also includes prior patent applications, including unpublished applications, in order to implement the first-to-file priority regime). Thus, on the face of the Act, the state of the art for purposes of obviousness corresponds exactly to the prior art that is relevant to anticipation, excluding prior unpublished patent applications.

The issue arose in this case because Phelan J had excluded two items of prior art from consideration at step 3 of the Windsurfing / Pozzoli test on the basis that they would not have been located in a reasonably diligent search [FC 214]. The FCA held that Phelan J had erred on this point.

Locke JA reviewed the Canadian case law, and noted that while a number of cases, including some affirmed by the FCA, had indeed excluded some elements of prior art, that point had never been specifically affirmed or even commented on by the FCA, and the point therefore could not be considered to be settled. My sense is that notwithstanding the text of the act, the Canadian courts have generally operated under the assumption that the codification was not intended to substantively change the law, and it is because of that underlying assumption that courts had not previously been pressed for a decision. Locke JA also noted that some decisions, including Ciba v SNF 2017 FCA 225 (see here) had suggested that the state of the art was broader in scope. However, none of these cases had definitively resolved the issue.

Locke JA also noted at [85] that “commentaries by authors well-known in the field of patent law have expressed doubt as to whether it is appropriate to limit the scope of relevant prior art to the results of a diligent search since the wording of section 28.3 of the Patent Act is not so limited.” I must say that I am disappointed that my own short article on this topic, “What is the State of the Art for the Purpose of an Obviousness Attack?” (2012) 27 CIPR Review 385-94, was not cited. In that article I pointed out that exactly that question was before the House of Lords in Technograph [1972] RPC 346 and English Court of Appeal in General Tire and Windsurfing [1985] RPC 59 in interpreting the parallel English legislation, which raised the same issue. Lord Reid and Lord Diplock took opposing views in Technograph, and the Court of Appeal in General Tire preferred Lord Reid’s view, but sided with Lord Diplock in Windsurfing. The point was expressly obiter in all these cases, and the point was never definitively resolved in English law prior to the adoption of the EPC with the Patents Act, 1977. The division of opinion in these decisions illustrates that the text itself is not determinative and it is unfortunate that the FCA did not devote more time to discussing these cases, which presumably were not cited to it. (While I did not come to a firm conclusion in my article, I had argued that the context of the enactment, in particular the history of the relevant English decisions on which Canadian law was based, suggested that the codification was not intended to alter the state of the art, but was only intended to establish the relevant dates for assessing obviousness, in particular to implement the grace period.)

Locke JA then addressed the substantive issue. I’ll set out the sentences of the key paragraph one at a time:

[86] In light of section 28.3 of the Patent Act and the applicable jurisprudence and commentaries, I conclude that it is an error to exclude from consideration prior art that was available to the public at the relevant date simply because it would not have been located in a reasonably diligent search.

This is clear: all prior art must be consided under step 3 of the obviousness analysis.

[86] The likelihood that a prior art reference would not have been located by a PSA may be relevant to consideration of step 4 of the obviousness analysis (whether differences between the state of the art and the inventive concept constitute steps which would have been obvious to the PSA) in that the uninventive PSA might not have thought to combine that prior art reference with other prior art to make the claimed invention.

This indicates that there can be no mosaicing of prior art that is not available in a reasonably diligent search. Thus, obviousness can be assessed over the common general knowledge alone, or over one item of broader prior art plus cgk, but not over two items of broader public art plus cgk. I believe that this is essentially the UK position.

Locke JA concluded with a policy point:

[86] However, excluding prior art simply because it is difficult to find is problematic because it would result in the possibility of a valid patent on an invention that had, but for some non-inventive tweak, already been disclosed to the public. In my view, that is not what Canada’s patent regime is intended to permit.

With respect, I do not find this persuasive. It is well-established that the mere fact that an item of prior art is “available to the public” does not mean that it is ever likely to be of any actual benefit to the public. “It is settled law that there is no need to prove that anybody actually saw the disclosure provided the relevant disclosure was in public. Thus an anticipating description in a book will invalidate a patent if the book is on a shelf of a library open to the public, whether or not anybody read the book and whether or not it was situated in a dark and dusty corner of the library.” Lux Traffic Controls [1993] RPC 107 at 133, quoted with approval in Baker Petrolite 2002 FCA 158 [42.6] (emphasis in Baker Petrolite). If there is prior art that would have made the invention obvious to a skilled person, but that would not be located in a reasonably diligent search, then it would only be located as part of an extended or arduous search. An invention may be found to be non-obvious because it would require experimentation that is “not routine, but rather was prolonged and arduous” Sanofi [89]. If that is true for experimentation, it is not clear why it should not be true for searching prior art. The traditional view is that the obviousness inquiry asks whether a person skilled in the relevant art would arrive directly at the invention when presented with the relevant problem. If the answer is no, I don’t see why it should matter whether that is the answer because discovering the invention would require prolonged and ardous technical experiments, or a prolonged and arduous prior art search plus routine experimentation.

On a related point, as noted above, the traditional inquiry was essentially factual, albeit focused on an objective skilled person, rather than any particular individual. The “state of the art” as being what would be discovered in a reasonably diligent search reflects what a skilled person would actually do when addressing the problem. If the state of the art includes all prior art, then we have moved away from this factual inquiry, into an odd hybrid, asking whether a skilled person would find the invention obvious in light of information which would not actually have been be available to them.

In any event, regardless of the policy issue, Locke JA’s conclusion is certainly supported by the text of the Act, and the point now seems to be settled.

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