If you Navigate to Tools > Worklist and the module you want to look at and you get a list of the active Notifications.
Is a flaw with the bell icon notification is that it is independant of email or worklist actions and doesnt reduce down. Unless it has been changed in R13
Mismatch Between Bell Notification And BPM Tasks? (Doc ID 2185023.1)
On : 220.127.116.11.0 version, Other Issues
Will there be any future updates to R11 to address the mismatch between Bell Notification and BPM Tasks?
As the logic in which the Task count are listed in both Bell icon and the BPM Tasks are different, it is difficult for the user to know what is the actual number of tasks that he needs to act on.
This is expected behavior only. We are not removing older notifications from BELL.
Please follow the navigation to see only active notifications
Navigate to Tools > Worklist and the module you want to look at and you get a list of the active Notifications.