Copied and source files are tracked so that authors of these documents can selectively update these files. Stale copied files can be eliminated. A control is provided to mediate copying of files among servers that have differing security policies. Metadata of a file being copied is downloaded from a server to the control and the control uploads the metadata of the file to one or more servers. A relationship between copied files and source files are memorialized whether or not copied files reside in different namespaces from the namespace of the source files.