US Patent 7954043 Concurrent editing of a file by multiple authors

A method, system and computer program product for enabling the concurrent editing of a document containing a plurality of independent or loosely connected segments by multiple authors is described. Among other things, the invention allows assigning of editing rights for each segment to a defined set of segment authors, making available a special segment that contains metadata shared by all the segments of said documents, and providing email means private to said document, for facilitating communication between the authors of the document.