In Prudential-LMI Commercial Insurance v. Superior Court, 51 Cal. 3d 674, 798 P.2d 1230, 274 Cal. Rptr. 387 (1990), the insured discovered, while laying carpet in 1985, that there was an extensive crack in the foundation and floor slab of an apartment building. The crack, it was learned later, was caused by expansive soil, and may have started shortly after the apartment complex was constructed in 1971. Prudential-LMI argued, among other things, that a suit limitation clause in its policy had expired and therefore coverage was denied. The suit limitation clause provided that suit must be brought within 12 months "next after inception of the loss." Id. at 680. The California court observed that some courts construing "inception of a loss" defined it as occurrence of the physical event causing the loss. Id. at 684. This strict construction approach, however, "may lead to an inequitable technical forfeiture of insurance coverage." Id. at 685. In contrast, in several California Court of Appeals cases the principle was advanced that the term "inception of the loss" means "that point in time at which appreciable damage occurs so that a reasonable insured would be on notice of a potentially insured loss." Id. The supreme court agreed, stating that "we agree that 'inception of the loss' should be determined by reference to reasonable discovery of the loss and not necessarily turn on the occurrence of the physical event causing the loss." Id. at 686. The court held that suit is timely if it is filed within one year after the "point in time when appreciable damage occurs and is or should be known to the insured, such that a reasonable insured would be aware that his notification duty under the policy has been triggered." Id. at 687. Determination of this point in time is a fact question. Id. at 687. The court cautioned that to take advantage of the delayed discovery rule, the insured must be diligent in the face of discovered facts. Id. In Prudential-LMI, the court noted that an additional provision of the policy in that case provided that suit must be commenced within 12 months "next after the happening of the loss." 51 Cal. 3d at 680 n.2. The court concluded, however, that there was "no legal difference" between "inception" and "happening" for purposes of resolving the issue before it, i.e., when does the one-year period begin to run in a progressive property damage case. Id. at 680 n.2. In Prudential-LMI Comm. Ins. v. Superior Court, the California Supreme Court was faced with a situation very similar to the one at hand, where it had to determine how long the suit limitation period on a property insurance policy should be tolled. In that case, the insured plaintiffs had received a letter from the insurer "proposing that coverage would be denied based on the . . . exclusion unless the insureds had any additional information that would favor coverage." Id. at 692, 274 Cal. Rptr. 387, 798 P.2d 1230. This letter began a series of negotiations between the insured and insurer, finally resulting in a formal and unequivocal denial some months later. The California Supreme Court elected to toll the running of the limitation period until the unequivocal denial, and not the denial that invited the submission of more information. Id. at 693, 274 Cal. Rptr. 387, 798 P.2d 1230.