The decision in Kaynes v. BP, PLC is a rare example of a limitation defence appropriately determined on a r. 21(1)(a) motion:
 In my opinion, as explained below, there are no material facts that could be pleaded or any discoverability issues that could or would postpone the running of the limitation period for the fraudulent misrepresentation cause of action. It is plain and obvious that all of the possible claims arising from the Deepwater Horizon disaster were discovered by June 1, 2012. In my opinion, as explained below, the case at bar is one of those cases where pursuant to rule 21.01 (1)(a), the court can and should strike a claim as statute barred.
The decision also provides an excellent overview of the distinction between the cause of action and the claim in the limitations scheme:
 Before the enactment of the current Limitations Act, 2002, a limitation period commenced when a cause of action accrued and when the cause of action was discovered.
 There are over a hundred causes of action and there were rules for when a cause of action accrued and rules about when an accrued cause of action was discovered. Prior to the enactment of s. 5(1)(a)(iv) of the current Limitations Act, 2002, the judge-made discoverability principle governed the commencement of a limitation period. The discoverability principle stipulated that a limitation period begins to run only after the plaintiff has the knowledge, or the means of acquiring the knowledge, of the existence of the material facts that would support a claim for relief; i.e. knowledge of the factual constituent elements of a cause of action. The discoverability principle conforms with the idea of a cause of action being the fact or facts which give a person a right to judicial redress or relief against another.
 A cause of action is a set of facts that entitles a person to obtain a judgment in his or her favour from a court exercising its common law, equitable or statutory jurisdiction. In Ivany v. Financiere Telco Inc., and 1309489 Ontario Inc. v. BMO Bank of Montreal, Justice Lauwers observed that the idea of cause of action is used in two related senses: (1) it identifies a factual matrix from which claims or complaints arise; and (2) it identifies the legal nature of those claims, which is the nominal or technical meaning of cause of action.
 With the enactment of the Limitations Act, 2002, a limitation period commences when a “claim” is discovered”. The words “cause of action” do not appear in the Act, and the goal of the legislators was that for the purpose of determining when a limitation period began to run, “claim” and “claim” discovery would replace cause of action accrual and cause of action discovery.  This goal, however, was not achieved and the case law continues to use the idea of a cause of action in association with the idea of a “claim” under the Act. Under the Act, a claim is discovered on the earlier of two dates: the day on which a plaintiff either knew or ought to have known the constitutive elements of the claim and that a proceeding in Superior Court would be an appropriate means to seek a remedy.
 This continued connection between the ideas of claims as defined by the Limitations Act, 2002 and causes of action as understood under statutes and in law and equity is understandable, because civil procedure requires a plaintiff to plead the material facts of a viable cause of action and just pleading that the defendant’s conduct harmed the plaintiff does not provide the plaintiff with a remedy for his or her legal grievance or give the defendant notice of the cause of action that he or she must defend.
 Section 1 of the Limitations Act, 2002 defines “claim” to mean: “a claim to remedy an injury, loss or damage that occurred as a result of an act or omission”. A claim is a function of cause of action, which is the fact or facts which give a person a right to judicial redress or relief against another. In Lawless v. Anderson, the Court of Appeal stated at paras. 22-23:
- The principle of discoverability provides that “a cause of action arises for the purposes of a limitation period when the material facts on which it is based have been discovered, or ought to have been discovered, by the plaintiff by the exercise of reasonable diligence. This principle conforms with the generally accepted definition of the term “cause of action” — the fact or facts which give a person a right to judicial redress or relief against another”….
- Determining whether a person has discovered a claim is a fact-based analysis. The question to be posed is whether the prospective plaintiff knows enough facts on which to base an allegation of negligence against the defendant. If the plaintiff does, then the claim has been “discovered”, and the limitation period begins to run: seeSoper v. Southcott(1998), 1998 CanLII 5359 (ON CA), 39 OR (3d) 737 (C.A.) and McSween v. Louis (2000), 2000 CanLII 5744 (ON CA), 132 OAC 304 (C.A.).
 Although functionally closely related to causes of action, a claim as defined under the Limitations Act, 2002 is somewhat different from a cause of action. A cause of action has discrete constituent elements. For example, as noted above, negligent misrepresentation has five specific constituent elements, but a claim under the Limitations Act, 2002 has just two generic elements; namely: (1) and act or omission of misconduct; and (2) injury, loss or damage caused by the misconduct. Strictly speaking, the application of the Limitations Act, 2002 does not require identifying the cause of action, it requires only determining whether the plaintiff has discovered wrongful conduct and harm for which a lawsuit would be appropriate to remedy the harm. Another difference between claims and causes of action is that all claims have the element of damages, but some causes of action are actionable without damages having occurred. The cause of action for contract, for instance, requires a contract and a breach of the contract; damages, which typically do occur when a contract is breached, are, however, not a constituent element of the cause of action for breach of contract. Another difference is that no causes of action have appropriateness of a lawsuit as a constituent element, which is a factor in what counts for a discovered claim under the Limitations Act, 2002. A subtle deviation between claim and cause of action is that discovery of a claim under the Limitations Act, 2002 requires the plaintiff to have knowledge of an occurrence of injury caused by the defendant’s misconduct for which a law suit would be an appropriate means to seek a remedy, but discovery of a cause of action under the common law requires the plaintiff to have knowledge that the defendant’s conduct occasioned the material facts of the constituent elements of a particular cause of action.
 All of the above reveals that the relationship between claim and cause of action is subtle and sometimes confusing. When a proceeding would be an appropriate means to seek to remedy, it is not enough for the plaintiff to just plead a claim as defined under the Limitations Act, 2002, he or she must still plead a reasonable cause of action. To assert a cause of action so as to interrupt a limitation period, the pleading must allege the facts necessary to identify the constituent elements of the cause of action.
 With some statutory adjustment, the discoverability principle continues to operate for claims, and the principle has been codified by the Limitations Act, 2002. Discoverability has been adjusted by s. 5(1)(a)(iv), and thus subject to s. 5(1)(a)(iv), a limitation period commences at its earliest when the plaintiff discovers the underlying material facts or, alternatively, when the plaintiff ought to have discovered those facts by the exercise of reasonable diligence, but because of s. 5(1)(a)(iv), discoverability may be postponed.
 Under the Limitations Act, 2002, 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.
 For the limitation period to begin to run, it is not necessary that the plaintiff know the full extent or quantification of his or her damages; rather, the period begins to run with the plaintiff’s subjective or objective appreciation of being damaged, i.e., of being worse off than before the defendant’s conduct.
 Section 5(1)(a)(iv) of the Limitations Act, 2002 adjusts the operation of the discoverability principle, and s. 5(1)(a)(iv) can have the effect of delaying the commencement of the running of limitation period. Where a person knows that he or she has suffered harm; i.e., when the plaintiff knows the elements of ss. 5(1)(a)(i),(ii), and (iii), the delay lasts until the day when a proceeding would be an “appropriate” means to remedy the harm having regard to the nature of the injury, loss or damage.
 The appropriateness factor of 5(1)(a)(iv) introduces some uncertainty in the operation of the Limitations Act, 2002 but it also introduces some flexibility and fairness in the application of the discovery principle, which presumptively operates against the claimant as soon as a cause of action becomes objectively apparent. In Markel Insurance Co. of Canada v. ING Insurance Co. of Canada, the Court of Appeal held that for s. 5(1)(a)(iv) to have a delaying effect, there must be a juridical reason for the person to wait; i.e., there must be an explanation rooted in law as to why commencing a proceeding was not yet appropriate. Appropriateness must be assessed on the facts of each particular case, including taking into account the particular interests and circumstances of the plaintiff.
 Subject to the adjustment made by s. 5(1)(a)(iv), with respect to the basic limitation period of two years under the Limitations Act, 2002, a claim is “discovered” on the earlier of the date the claimant knew – a subjective criterion – or ought to have known – an objective criterion – about the claim. Pursuant to s. 5(2) of the Act, the discovery of a claim presumptively occurs for the plaintiff on the date of the act or omission, but the plaintiff may rebut the presumption by demonstrating that he or she could only have reasonably discovered the underlying material facts after the date of the act or omission.
This is the impact of the distinction:
 Applying these principles to the circumstances of the immediate case, pursuant to the Limitations Act, 2002 around June 1, 2010, presumptively and also subjectively and objectively factually, Mr. Kaynes discovered he had a “claim” against BP. He subjectively knew that BPs misconduct had caused him harm and he knew that court proceedings would be appropriate. For the purpose of the commencement of limitation periods, it was not necessary for Mr. Kaynes to put a cause of action name to his “claim”. Whatever way the statement of claim was later framed to name a cause of action, the “claim” to which the cause of action was connected had been discovered in 2010 and the limitation period clock was running.
 In other words, having discovered a “claim” in 2010, Mr. Kaynes had two years to plead the misconduct connected to the claim by pleading the material facts of negligence, negligent misrepresentation, fraudulent, misrepresentation, an oppression remedy, nuisance, or whatever. For the purpose of commencing a proceeding, however he might label his claim as a cause of action in a statement of claim, the limitation period for the “claim” was running by June 1, 2010. As it happened, albeit late, in November 2012, Mr. Kaynes pleaded a cause of action for negligent misrepresentation in Ontario, and he gave his claim a cause of action name, but regardless of its name in accordance with the principles of the Limitations Act, 2002, the negligent misrepresentation claim was already statute barred. A fraudulent misrepresentation claim had it been pleaded in November 2012 in Ontario would also have been statute barred.
The court also found that uncertainty as regards forum does not impact on appropriateness (consistent with Lilydale Cooperative Limited v. Meyn Canada Inc., which held similarly but isn’t cited in the decision):
 In a creative argument, Mr. Kaynes, however, argues that his April 2012 action in Alberta was a timely claim in Alberta, with which I would agree, and until the Alberta court declined to take jurisdiction with respect to that claim, which did not occur until November 2012, it could not be said that a claim in Ontario had been discovered until November 2012. In this regard, he submits that under s. 5 (1)(a)(iv) of Ontario’s Limitation Act, 2002, it was only after Alberta declined to take jurisdiction that it could be said that proceedings in Ontario were appropriate and thus until the November decision in Alberta, the claim in Ontario had not been discovered.
 This argument, however, does not work because the appropriateness of a proceeding in Ontario is not determined by the inappropriateness of a proceeding somewhere else. If any, the decision in Alberta, confirmed that Ontario was the appropriate forum for proceedings against BP.