In order to view all the groups an entity belongs to a custom sublist can be used. Here are the steps:
1. Create a Group Saved Search by navigating to List > Search > Saved Searches > New > choose Group.
2. Under the Available Filters add Group Members : Internal ID.
3. Check the Available As List View and set to Public then Save.
4. Navigate to Customization > Forms > Sublists > under the Entity tab add the Group Search created.
5. Specify a Label and indicate as to what tab it will be displayed.
6. Make sure Customer, Employee and Contact are checked.
Navigate now to a Customer record and it shows a list of Group that Customer belongs to. This would include both dynamic and static groups.