Allow personal annotation for shared files
Users are allowed to run notes on the shared files but the notes are available for personal view only and not shared like the files.
This way, users would have personal notes not visible to others but will have a single source for the actual shared file.
Example, I would be sharing files and discussing it over a meeting. Users can put notes on the shared files as we go along, but then these notes are available for their use only. Notes from other users are not shared, only the file.