the attribute values a period of validity for the signing of the electronic property by alice a name of the subject of the empowerment certificate may optionally be included this could be the name of alice if she is acting in a given capacity a period of validity of the ownership may also be included this could be a finite period of use or a permanent assignment of ownership in which case the period is open ended the ec 806 empowers bob to obtain the values of the attributes defined in the ec 806 the attributes include alice 39 s public key value and alice 39 s name as recorded as owner of the electronic property additional attributes can also be empowered by alice it should be understood that an attribute has a name or identifier and an attribute value the ec 806 contains the attribute identifier and the attribute value is supplied by the ra source to the relying party the ec 806 contains the name of the assignee bob of the electronic property 801 and may contain the name of the assignor alice an automated system can use the facilities of the empowerment infrastructure to check that the assignment is bona fide and not forged and to establish whatever attributes of alice and bob that are required as long as they have been empowered by alice this is done by bob obtaining a custom certificate once bob has received the ec 806 he obtains a custom certificate based on the ec 806 custom certificates are described.