The person that owns the front doors of a building owns the entire building.

The person that owns the front doors of a building owns the entire building and is therefore entitled to all doors within the building.

If a building has no readily apparent front doors, the owner of any interior doors has the claim to the ownership of the base.

In the event that multiple people own interior doors, the person owning the highest amount of doors that are accessable without opening any further doors owns the base.