Unowned property refers to tangible, physical things which are capable of being reduced to being property owned by an individual, but are not owned by anyone. Nearly every piece of land on the Earth is property and has a maintainer (/owner). The class of objects, "Unowned Things", are objects which are not yet property; either because it has been agreed by sovereign nations that no one can own them, or because no person, or other entity, has made a claim of ownership.