You may get notified that you need to log back in and eliminate duplicate entries — or have a service provider do it for you. The email states:
“Google Places no longer accommodates more than one authorized owner per business location. Your account contains one or more listings that have been identified as duplicates of other listings and as a result, some of the information you provide will not be shown to Google users anymore…”
The full details can be found on Google’s product forums.