Federal Rule of Civil Procedure 23(f)’s 14-day limit on petitioning for leave to appeal from a class certification or here, decertification, order is not jurisdiction since it is set by a rule rather than a statute. As it is not jurisdictional, the deadline may be equitably tolled. A reconsideration motion filed before the end of the 14-day deadline will toll the petition deadline until after the motion is denied. Also, the deadline can be tolled by a reconsideration motion that is filed outside the 14-day period if, during that period, the would-be appellant told the district court he wished to move for reconsideration and stated, even if briefly, the ground for doing so, and the district court then set a deadline for filing the reconsideration motion which was beyond the 14-day time limit. This decision reverses an order decertifying a class action under the unfair competition law and false advertising law seeking a full refund of the purchase price of an aphrodisiac that had been marketed without adequate testing to back its sexual enhancement claims. Uncertainty regarding class members’ damages does not prevent certification of a class as long as a valid method has been proposed for calculating those damages. In particular, under the UCL and FAL only some reasonable basis for computation of restitution is required, and even an approximation will suffice. Here, the full refund method was consistent with plaintiff’s theory of liability. Plaintiff showed evidence of the defendant’s suggested retail price as well as the retail prices plaintiff individually paid for the product. That was enough to show plaintiff had a workable method for assessing damages. He was not required to present proof of an average retail price for the product.