Experts play an important role in IP litigation, but the court will carefully consider whether the proposed expert evidence is necessary to assist the trial judge and has demonstrated an increasing willingness to determine, before the trial, that expert evidence will be excluded. Careful assessment of the need for expert evidence will lead to efficiencies, and is consistent with the Federal Court's stated goal of achieving increased proportionality in complex litigation. For businesses managing litigation budgets, this should translate to lower costs to assert and defend IP rights.


Association of Chartered Certified Accountants et al. v. The Canadian Institute of Chartered Accountants et al., 2016 FC 1076 [ACCA]

IP Type



The ACCA case involves uniquely Canadian "official marks". Official marks, also known as prohibited marks, provide powerful trademark rights that trump all others, reserved for "public authorities". To qualify as a public authority, an entity must be under a degree of government control.

The plaintiffs served expert reports from two law professors on the issue of government control, offering the opinion that the defendants did not operate under a sufficient degree of government control to qualify as a public authority. Both reports were ruled inadmissible on a pre-trial motion, essentially because they were legal arguments guised as evidence.

The result in the ACCA case is consistent with the outcome in a recent decision of the Federal Court of Appeal relating to use of funds by a federal political party: Canada (Board of Internal Economy) v. Canada (Attorney General), 2017 FCA 43. In that case, the evidence of a law professor on the issue of comparative constitutional law was also held to be inadmissible on a pre-hearing motion, as it was effectively a legal opinion—i.e., the very expertise of the judge.