(B) Contingent payments. In accordance with paragraph (1)(iv)(A) of this section, a provision of a written contract described in paragraph (k)(1) of this section, or of the additional documentation described in paragraph (k)(2) of this section, that provides for payments for a PCT (or group of PCTs) to be contingent on the exploitation of cost shared intangibles will be respected as consistent with economic substance only if the allocation between the controlled participants of the risks attendant on such form of payment is determinable before the outcomes of such allocation that would have materially affected the PCT pricing are known or reasonably knowable. A contingent payment provision must clearly and unambiguously specify the basis on which the contingent payment obligations are to be determined. In particular, the contingent payment provision must clearly and unambiguously specify the events that give rise to an obligation to make PCT Payments, the royalty base (such as sales or revenues), and the computation used to determine the PCT Payments. The royalty base specified must be one that permits verification of its proper use by reference to books and records maintained by the controlled participants in the normal course of business (for example, books and records maintained for financial accounting or business management purposes).