With the existence of user rules, it might be necessary to change the file owner in order to change its effective rule. For example, if there is a file that needs to have a permanent exclusive rule, the file can be moved to an owner who has a permanent exclusive rule. Changing file ownership is available for everyone who has manager permission on the folder.
File ownership change is a logged operation. You can see it in the transaction tab and search for it from the Audit Manager.