Patent Center conveniently uses a standard URL format for patent applications. The URL structure is https://patentcenter.uspto.gov/#!/applications/XXXXXXXX, where XXXXXXXX is the application number. That URL points to the application-data page of the specified application. This permalink can be really useful.
Unfortunately, however, if a user attempts to use that link structure to access an application number for an application that the user does not have the right to access, the Patent Center web server returns a completely blank screen rather than just returning the Patent Center home page or login page. I recommend that the PTO revise the underlying logic to have the server return the Patent Center home page or login page in this situation. That would be much more user friendly and helpful.