A method and a system for sharing files recorded by non-divisible sections in a first memory, including dividing each section into subsets to which are respectively assigned specific access rights; storing, in a second memory, separate from the first one, a specification table comprising at least the location of each subset in the section, at least one key conditioning the access to this subset, and the rights assigned to the key; and conditioning the accesses to the subsets to their respective specifications by a control performed by a microprocessor.