Limitations - Discoverability
Gillham v. Lake of Bays (Township) (Ont CA, 2018)
In this Court of Appeal case the court canvasses general principles of discoverability under limitations law:
 In his discoverability analysis, the motion judge was required to consider the provisions of s. 5(1) of the Act, in the light of the governing principles regarding discoverability.
 Section 5(1) of the Act provides as follows:
(1) A claim is discovered on the earlier of, The overarching question in the discoverability analysis under s. 5 of the Act is whether the claimant knew or reasonably should have known, exercising reasonable diligence, the material facts stipulated under s. 5(1)(a) that give rise to a claim: Ferrara v. Lorenzetti, Wolfe Barristers and Solicitors, 2012 ONCA 851 (CanLII), 113 O.R. (3d) 401, at para. 32. Section 1 of the Act defines a claim as “a claim to remedy an injury, loss or damage that occurred as a result of an act or omission”. Section 2(1) provides that the Act “applies to claims pursued in court proceedings” (with certain enumerated exceptions that do not apply here).
(a) the day on which the person with the claim first knew,
(i) that the injury, loss or damage had occurred,
(ii) that the injury, loss or damage was caused by or contributed to by an act or omission,
(iii) that the act or omission was that of the person against whom the claim is made, and
(iv) that, having regard to the nature of the injury, loss or damage, a proceeding would be an appropriate means to seek to remedy it; and
(b) the day on which a reasonable person with the abilities and in the circumstances of the person with the claim first ought to have known of the matters referred to in clause (a).
 Knowledge of the claim includes knowledge of the identity of a potential defendant, although it is not necessary for a claimant to know with certainty a potential defendant’s responsibility for an act or omission that caused or contributed to the loss. As this court observed in Longo v. MacLaren Art Centre, 2014 ONCA 526 (CanLII), 323 O.A.C. 246, at para. 44: “All that is required is that the plaintiff has prima facie grounds to infer that the acts or omissions were caused by the identified parties.”
 While neither the extent nor the type of loss need be known, the claimant must know that some non-trivial loss has occurred, and that a proceeding would be a legally appropriate means to seek to remedy it: Markel Insurance Company of Canada v. ING Insurance Company of Canada, 2012 ONCA 218 (CanLII), 109 O.R. (3d) 652, at para. 34. The common law acknowledges that trivial damages do not trigger a limitation period, since a prudent plaintiff would not bring an action to recover a trivial loss: Grey Condominium Corp. No. 27 v. Blue Mountain Resorts Limited (2007), 2007 CanLII 5368 (ON SC), 277 D.L.R. (4th) 644 (Ont. S.C.J.), aff’d 2008 ONCA 384 (CanLII), 90 O.R. (3d) 321, at para. 58.