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Posted in: Intellectual Property

Jan 24, 2018

Canadian Patent Appeal Board Adopts a New Approach to Attack Patents for Lack of Utility

By Erica L. Lowthers, PhD


In order for a factual basis and/or sound line of reasoning for predicted utility to be considered sufficiently disclosed in the common general knowledge and, therefore, not required to be disclosed in the specification, the PAB has taken the position that the subject matter must be “generally known and accepted without question by the bulk of those who are engaged in the particular art.”

In Canada, as in most other jurisdictions, a claimed invention must be useful; this is usually a minimal requirement that is easy to meet. In Canada, when utility is not demonstrated through examples in the specification, it must be soundly predicted as of the Canadian filing date.

It is well-accepted that sound prediction requires three components, as set out in Apotex Inc. v. Wellcome Foundation Ltd., 2002 SCC 77 (paragraph [70]):

Firstly ... there must be a factual basis for the prediction ... Secondly, the inventor must have at the date of the patent application an articulable and 'sound' line of reasoning from which the desired result can be inferred from the factual basis ... Thirdly, there must be proper disclosure.

The precise ambit of “proper disclosure” has been litigated extensively with respect to whether the factual basis and sound line of reasoning must be found in the specification. Although perhaps not entirely settled, the general consensus is that these components must be disclosed in the specification unless they form part of the common general knowledge.

The last 15 years have seen a heightened requirement for usefulness in Canada, where any statements of utility in the description of a patent would be construed to determine whether these amounted to a promise of utility. If such statements were construed as promises, then those promises acted as the yardstick against which the utility of the claims would be measured. This came to be known as the “Promise Doctrine.”

A landmark decision by the Supreme Court of Canada (AstraZeneca Canada Inc. v. Apotex Inc., 2017 SCC 36; blogged about here), struck down the Promise Doctrine as being “punitive,” “antagonistic to the bargain on which patent law is based,” and “not good law.” This decision was celebrated by patentees and patent agents alike. Despite this, sound prediction remains good law and many of us in the profession have been watching decisions related to utility to see if the Courts or the Canadian Patent Appeal Board (PAB) might have an appetite for sustaining attacks based upon lack of utility. The PAB, it seems, does have such an appetite.

In Commissioner’s Decision No. 1437, Canadian Patent Application No. 2,454,678 was refused for lack of utility. Claim 1 reads as follows:

A method for the adaptation of bacteria for use in the leaching of ores and concentrates, the method characterised by the steps of:

a) Obtaining samples of bacteria exhibiting salt tolerance;

b) Combining the bacterial samples from step a) with a stock bacterial culture known to have the ability to oxidise sulphide minerals; and

c) Growing the combined culture of step b) over time in saline conditions to produce an adapted stock bacterial culture that expresses salt tolerance in addition to its ability to oxidise sulphide minerals.

The PAB stated, in paragraph [74], that:

Claims 1 and 4 assert the utility to be the production of "an adapted stock bacterial culture that expresses salt tolerance in addition to its ability to oxidise sulphide minerals." We are of the view that the person skilled in the art would understand this to mean that the defined methods will result in an adapted stock bacterial culture that is both "salt tolerant" and able to oxidize sulphide minerals.

Rightly so, the PAB steered well clear of arguing that specific promises were not met and mentioned the Supreme Court’s AstraZeneca decision only once. Instead, the PAB focused on whether there was a proper disclosure of the factual basis and sound line of reasoning for the construed utility in the specification and, perhaps not surprisingly, found that there was not.

Therefore, the PAB discussed in detail the definition of “common general knowledge” and whether the factual basis and sound line of reasoning could be found there. In doing so, the PAB cited Uponor AB v. Heatlink Group Inc., 2016 FC 320, which itself cited Eli Lilly and Company v. Apotex Inc., 2009 FC 991, which in turn cited several earlier cases relating to this issue. Although these cases related to common general knowledge and how it may differ from a citable reference with respect to novelty and obviousness, the PAB applied them without much explanation as to how the common general knowledge relates to the disclosure of a factual basis and sound line of reasoning for assessing sound prediction of utility.

The PAB identified in these cases the statement that, for something to be considered common general knowledge, it must be “generally known and accepted without question by the bulk of those who are engaged in the particular art.” The PAB argued that since there is no evidence that the factual basis and sound line of reasoning were “accepted without question,” they could not be considered part of the common general knowledge.

Interestingly, however, Eli Lilly had in fact affirmed a tempering of the definition that common general knowledge must be “generally accepted without question” and instead held that it must, rather, be “generally regarded as a good basis for further action.” This is a lower bar than that which was held by the PAB and was not addressed in the decision.

Moreover, the claims in question are method claims and their language appears to guarantee that only those combined cultures that “produce an adapted stock bacterial culture that expresses salt tolerance in addition to its ability to oxidise sulphide minerals” would fall within the scope of the claims. Utility should truly be a non-issue here, since any combined culture that does not have the recited utility is excluded from the scope of the claims and only useful cultures are explicitly claimed.

Furthermore, the PAB seems to be asserting that the utility here relates to whether the invention could be made, rather than whether the invention in its full scope, would work. This is misguided, as explained in Laboratoires Servier, Adir, Oril Industries, Servier Canada Inc. v. Apotex Inc., 2008 FC 825 (affirmed, 2009 FCA 222).

Hopefully this case will be appealed so we can see further debate on these issues and guidance from the Federal Court. Absent such guidance, this will likely be a new path that Examiners in Canada will be following. 

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