The maximum number of Address Objects within an Address Group is 1000, including the Address Objects from nested Address Groups. For nested groups, not exceeding 150-200 objects per group is recommended, having 5 nested groups of that size as the limit to not exceed the maximum of 1000 entries in the parent group. We recommend keeping Address Groups to a minimal size consisting of sets of Address Objects that are relevant to usage in multiple areas of the configuration, such as Access Rules, App Rules, Routes, etc.
If a larger set of Address Objects is required, instead of creating a new large Address Group containing only Address Objects, we highly recommend grouping existing Address Groups into a parent Address Group.