this is the expected behaviour. The most common use-case is that every user has his own basket. DocuWare changed this behaviour to the one you would like in 6.11 or 6.12, but due to a large backlash from the community changed it back to what you see right now in 7.0.
Currently, I am not aware of any way to disable this, but I also never actively searched for it. Maybe some DocuWare employee can help here.
Greetings from Germany,
Simon H. Hellmann
DocuWare System Consultant