How does BeaconManager handle Regions?

Hi,

I understand the general idea of Regions but I'm not sure about the implementation details for two of the methods of the BeaconManager:

1.
BeaconManager.startMonitoring(Region region)
The region provided here is added in any case. If there is a region having the same (region) identifier, it will be removed. Every BeaconManager object shares the same set of regions being monitored.
Is that right?

2.
BeaconManager.stopMonitoring(Region region)
The API is somehow unclear here:
"The object you specify need not be the exact same object that you registered but its beacon region attributes should be the same."
What exactly are beacon region attributes? proximityUUID, major and minor?

Thanks in advance!