First possession theory of property
The "first possession" theory of property holds that ownership of something is justified simply by someone seizing it before someone else does. This contrasts with the labor theory of property where something may become property only by applying productive labor to it, i.e. by making something out of the materials of nature.

Real property 

Pedis possessio is a legal phrase in common law used to describe walking on a property to establish ownership; this concept involves the establishment of first possession of land. By walking on a property and defining its bounds, possession is established. Legal dictionaries put forth this definition. Pedis possessio has been described as the actual possession of land within bounds set forth by the need of a mine claimant and operator to improve and work a claim for its mineral value.

Violation of set boundaries are avoided and violence prevented by the establishment of title using the concept of pedis possessio.

See also 

 Adverse possession
 Labor theory of property
 Terra nullius
 Utilitarian theory of property

References 

Latin legal terminology
property
theories of law