Also known as: res propria · private property · res propria vs res communis
Written by attorneys · grounded in primary & secondary sources — see below
A Latin maxim declaring that private property consists of those things not held in common. The maxim identifies the boundary between property subject to individual ownership and resources open to public use. It supplies the conceptual foundation for determining when government action affecting an asset triggers constitutional protections for private property.
Rita Russell owns subsurface mineral rights beneath developed land. A statute bars extraction that would cause surface subsidence. The court applies the maxim to classify the mineral estate as private property rather than a common resource and holds that the restriction effects a taking requiring just compensation.
Roland Rhodes, commanding a privately commissioned vessel, seizes enemy cargo during declared hostilities. He asserts sole title to the captured goods. The court applies the maxim to hold that prize taken without sovereign commission remains common rather than private property and therefore belongs to the United States.
Select any source to read its text and confirm it supports the definition.
Rebecca Ross owns a parcel subject to a new ordinance that prohibits construction above a certain height. The city claims the airspace is a common resource. The court treats the airspace as private property under the maxim and finds the restriction effects a taking.
Riverstone Manufacturing owns subsurface mineral rights beneath developed land. A statute bars extraction that would cause surface subsidence. The court holds the restriction effects a taking because the maxim classifies the mineral estate as private property that cannot be rendered valueless without compensation.
Royal Crest Hotels owns waterfront parcels targeted for a municipal redevelopment plan. The city condemns the land and transfers title to private developers. The court sustains the taking after finding the project serves a public purpose, treating the parcels as private property subject to the just-compensation requirement.
Raven Logistics owns a lot abutting a planned municipal street widening. The city takes a strip for the roadway and offers no payment. The court applies the maxim to classify the strip as private property and requires just compensation under the incorporated Fifth Amendment.
The maxim applies to any asset that is not held in common. Primary authorities treat both real estate and personal property, such as drug inventory or client funds, as private when they are not open to public use.
Supporting sources
A permanent physical occupation or compelled transfer of title effects a taking because the asset ceases to be private. Recurring access rights and outright appropriations likewise destroy the owner's exclusionary interest.
Supporting sources
No compensation is due when the state destroys property in an emergency to avert serious public harm. The maxim still classifies the asset as private, but the necessity defense removes the obligation to pay.
Supporting sources
…the Appellate Division and upheld the law. This Court noted probable jurisdiction. II The Fifth Amendment provides that "private property [shall not] be taken for public use, without just compensation." It is well settled that the government may impose regulations on private property that substantially advance legitimate…