(I actually think this might be a bug...)
Note: Org-wide defaults on accounts/contacts/opportunities/cases are all set to "Private".
I have the following role hierarchy:
As expected, Team Lead 3 cannot see contacts owned by Team Lead 2, even if Team Lead 3 owns the account.
However, if I create the following sharing rule...
...suddenly Team Lead 3 AND Team 3 / Group 2 BDA can see all contacts (not opportunities or accounts) owned by the other Team Leads AND their subordinates. If I delete this rule, the sibling access issue goes away. I don't understand how a sibling's access would be exposed when it is on a completely different hierarchy than the roles in the rule.
Does anyone have any insight? Is this a bug or am I misunderstanding something here?