B7 A contractual restriction on an entity’s ability to direct an asset for another use
must be substantive for the asset not to have an alternative use to the entity. A
contractual restriction is substantive if a customer could enforce its rights to the
promised asset if the entity sought to direct the asset for another use. In
contrast, a contractual restriction is not substantive if, for example, an asset is
largely interchangeable with other assets that the entity could transfer to
another customer without breaching the contract and without incurring
significant costs that otherwise would not have been incurred in relation to that
contract.
IFRS 15