When you are in the Policy Manager of the Oracle Identity Management Suite and you want to add a group you REALLY need to know that there is a hidden link on this page. Try to find it yourself in the next picture:
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Found it?
No?
Let me give you a hint. Look in the blue band and search for some blue text :-)
I'm not sure if anybody knew about this. I checked the documentation, and nothing about adding a group to such an Authorization Rule for groups is written in there.
I wonder if anybody at Oracle knows about this hidden gem.
I will log an SR with Support and also mail some people I know at Oracle to discuss this perfect piece of user interface design.