US Patent 8935214 Storing electronic content with time-varying properties

Systems and methods for controlling document storage and tracking model dynamic attributes of a document in a time-varying manner, and enable reconstruction of a document's state at any point in time. The time-varying model identifies dynamic components of documents, where dynamic components include time-varying properties that changes over time. A set of validity parameters are associated with each state of a document (the state of a document corresponds to a new version of the document that results from changes to the document), and the set of validity parameters define a validity period for the state. Instead of archiving each new version of the document that corresponds to each new state of the document, the document is archived in storage by archiving information of the states along with the set of validity parameters corresponding to each state.