A method, apparatus, system, and signal-bearing medium that, in an embodiment, create an amalgamated file based on differences between versions of files. When an edit command directed to the amalgamated file is received, the file to which the edit command applies is determined and a change tag is added...http://www.google.de/patents/US20060064634?utm_source=gb-gplus-sharePatent US20060064634 - Editing multiple file versions
