The Account Ownership checkbox grants account viewing and editing privileges to a contact. If the contact is not the account owner, they are not able to view and edit account information. The can only view files shared with them.
For example, if there is another party involved with the account, such as a spouse, and the spouse needs access to the account but is not the primary contact for communications, you would grant them Account Ownership privileges using the Account Ownership checkbox.
Contacts with Account Ownership can see and edit basic Account information on the Desktop Version of Liscio. (not including sensitive information like SSNs, EINs, Accounting Information, etc.)