The recording time of charges for the use of intellectual property follows the substance of the license agreement. However, if the rights to use intellectual property are sold or purchased outright for a fixed fee, under a non-cancellable contract, and where the licensor has no remaining obligations to perform, then the whole sum is reported as a sale or purchase in the period of the acquisition or disposal. Otherwise, charges are allocated over the life of the agreement. In practice, it may be feasible to record the payments only when they are made.