What is the standard of review for patent litigation in Canada?

In Canada patents are administratively granted by the Commissioner of Patents. Yet administrative law principles have never been applied when determining the validity of a patent during litigation. Courts have always proceeded on the basis of a trial de novo to determine whether (on a balance of probabilities) the patent was indeed valid and properly granted. This paper examines the apparent tension between the Patent Act, patent jurisprudence and administrative law principles in litigating the validity of a patent.