Res extra commercium (lat. "a thing outside commerce") is a doctrine originating in Roman law,[1] holding that certain things may not be the object of private rights, and are therefore insusceptible to being traded. The doctrine encompasses entities such as humans, public areas, organs, citizenship, and prostitution, and is an exception to the general principle of freedom of contract.
The doctrine can also refer to areas beyond national borders, such as space and the seabed: "these regions are subject to a common freedom of exploitation without exercising national sovereignty."[2] If the world community is conceived as made up "of sovereign, territorial states ... [the implication is] that the space between these states is res extra commercium, a space that, because of its position and function within this community, is disassociated from the full package of rights to possession, exclusion, and alienation that normally may be claimed by holders of property."[3]