What is the test for discoverability of a claim?

Furthermore, the degree of knowledge required in order to require notice would be set too high. In Johnson v. Studley, [2014] O.J. No. 1232, OSCJ Perell J. stated: 59. The discoverability of a claim for relief involves the identification of the wrongdoer and also the discovery of his or her acts or omissions that constitute liability. It is not enough that the plaintiff has suffered a loss and has knowledge that someone might be responsible; the identity and culpable acts of the wrongdoer must be known or knowable with reasonable diligence. 60. However, the discovery of a claim does not depend upon the plaintiff knowing that his or her claim is likely to succeed; the limitation period runs from when the prospective plaintiff has or ought to have had, knowledge of a potential claim, and the later discovery of facts which change a borderline claim into a viable one does not give rise to the discoverability principle. The question is whether the prospective plaintiff knows enough facts to base a cause of action against the defendant, and, if so, then the claim has been discovered and the limitation period begins to run. 61. For the limitation period to begin to run, it is enough for the plaintiff to have prima facie grounds to infer that the defendant caused him or her harm, and certainty of a defendant's responsibility for the act or omission that caused or contributed to the loss is not a requirement.