Presumption of validity in Canadian patent law
The presumption of validity refers to the fact that, once a patent has been issued, the courts will presume that it is valid, unless there is evidence to the contrary. Canada. Section 43(2) of the "Patent Act" creates the presumption of validity: In "Diversified Products Corp v Tye-Sil Corp", the Federal Court of Appeal held that the presumption of validity merely gives rise to an evidential burden on a balance of probabilities.