A method and apparatus for maintaining control of a record which may have transferable value wherein the system provides for digitally signing a record in a partially-trusted distributed environment and allows a single unique authoritative copy to be held at a repository. The system meets the uniqueness...http://www.google.fr/patents/US7146500?utm_source=gb-gplus-shareBrevet US7146500 - System for obtaining signatures on a single authoritative copy of an electronic record
System for obtaining signatures on a single authoritative copy of an ...
