Patent Experts

My recent column on the use of experts in patent cases was published last week on It touches on some of the recent developments in this area including the updated guidelines on experimental testing, blinding of experts and number of experts in bifurcated proceedings.

The article, Crucial Patent Experts, was originally published on Slaw on July 8, 2016. It is reproduced below:

Crucial Patent Experts

Patent cases focus on the expert evidence. In many cases, the key issues of claim construction, the applicability of the prior art and infringement all turn on the evidence provided through the opinions of expert witnesses. There are several interesting issues arising recently in the use of experts in intellectual property cases.

The Federal Court of Appeal has recognized the unique position of expert evidence in patent cases, stating: “the practical reality is that a court nearly always reads a patent through goggles supplied by the experts whom the judge considers to be credible and accurate” and “The skilled reader approaches the patent with an appreciation of the common general knowledge in the art to which the patent relates. This is not within the purview of a judge, so almost always the parties adduce expert evidence to explain how the skilled reader would read and understand the patent” (ABB Technology AG, ABB Inc. v. Hyundai Heavy Industries Co., Ltd., 2015 FCA 181 at paras 25 and 26).

As has long been the practice, expert reports must be exchanged prior to trial. The timing of the reports is fixed in the Federal Courts Rules, but is often varied through a scheduling order during the course of the case management process. These reports must include a ‘code of conduct’ signed by the expert in which they acknowledge their role to assist the court.

The Rules also require that any objections to reports be raised as early as possible in the proceeding, including at the pre-trial conference (Rule 52.5). The Federal Courts Rules also provide for various non-traditional modes of expert testimony including a conference between the experts prior to the hearing or the testifying of experts as a panel (Rule 282.1). These non-traditional modes have been rarely used since they were introduced in 2010. A couple of examples where experts were examined in a ‘hot tubbing’ format includes a damages proceeding in Apotex Inc. v. Astrazeneca Canada Inc.,2012 FC 559 by Justice Hughes and of accounting experts for a copyright counterclaim by Justice de Montigny in Distrimedic Inc. v. Dispill Inc., 2013 FC 1043.

The Federal Court has recently updated its guidelines on the use of testing or experiments prior to hearing. The guidelines require that notice any experimental testing be provided to the other side at least two months prior to the exchange of expert reports. This is to permit opposing counsel and experts to observe the testing. Although not yet updated on the Federal Court’s website, these guidelines were amended to clarify that the case manager may vary the notice periods so the case manager could take into account the proceeding’s schedule. Failure to notify the other side could result in the evidence not being admissible.

Both the Federal Courts Rules (Rule 52.4) and the Canada Evidence Act(s.7), limit parties to five experts unless leave is sought. Recently, inEurocopter v. Bell Helicopter Textron Canada Limited, 2016 FC 590, the court clarified that this limit applied across bifurcated proceedings. In other words, if a case has been split into a liability phase dealing with claim construction, patent validity and infringement, and a quantification phase dealing with the extent of infringement and damages, then the total number of experts in both phases is limited to the five, unless leave is obtained. This ruling will likely require litigants to look more closely at their use of experts during the liability phase of bifurcated proceedings and perhaps pre-emptively address the issue of experts in bifurcation orders.

Another issue being addressed recently is the ‘blinding’ of experts, an issue raised by the Federal Court at its recent ‘Town Hall’. Experts are ‘blinded’ by being asked their opinions on certain issues without providing them all of the information for the case, only what is necessary for that specific opinion. For example, an expert may be asked to provide their opinion on claim construction without seeing the prior art or the allegedly infringing product. A series of cases have discussed how evidence from blinded experts is to be compared to evidence of non-blinded experts. In a pair of cases released in April of this year, Justice Zinn and Justice Locke commented on the weight of blinded experts. Justice Zinn stated, “this court has recognized that evidence from experts who have not seen the patent nor been apprised of the positions of the litigants is to be given greater weight on issues going to obviousness and patent construction than the evidence of an expert with full knowledge of the patent’s disclosure and the positions of the parties” (Allergan Inc. v. Apotex Inc., 2016 FC 344 at para 13). Justice Locke comment that, “I agree with Shire that favouring the evidence of experts who have been blinded has not been raised to the level of a legal principle that must be applied in all cases, and is merely persuasive … I am mainly interested in the substance of an expert’s opinion and the reasoning that led to that opinion. If it is well-reasoned, there may be no reason for concern about whether the witness was blinded to certain facts when giving the opinion. A concern may arise where the expert’s opinion seems tortured or less well-reasoned.” (Shire Canada Inc. v. Apotex Inc., 2016 FC 382 at para 45)

As the area of law develops around the role of expert evidence in patent cases, it is important to work carefully with experts to ensure that their opinions are found credible and given weight by the trial judge. A misstep can result in the expert evidence being considered inadmissible, leaving key aspects of the case without evidence.