Appropriation

Appropriation (economics) - Wikipedia

Libertarian and other property-rights-oriented ideologies define appropriation as requiring the “mixing” of the would-be owner’s labor with the land claimed. A prime example of such mixing is farming, although various extractive activities such as mining, and the grazing of herds are often recognized. Personal, physical residence is often recognized after some minimum documented continuous period of time, as is the erection of dwellings and other buildings on land whose ownership has not previously been recognized by the authority whose recognition is sought.

なるほどー。しかし、やはり適切な訳が思いつかない。