5Where property in respect of which compensation is payable as aforesaid was, immediately before the acquisition thereof by the Secretary of State, in the possession of some person by virtue of a hire purchase agreement, that person may, by a notice served on the Secretary of State, make a claim to have apportioned to him such part of the compensation as may be specified in his claim; and in default of agreement between the parties the claim shall be determined by arbitration, and the arbiter may apportion the compensation between the owner and the other person in such manner as appears to him to be just.