Numerus clausus of real rights

The numerus clausus of real rights means that private parties cannot invent new property rights with erga omnes effect at will. Swiss property law provides a closed catalogue of recognised real rights, including ownership, easements, usufruct and security rights. Parties may shape contractual obligations creatively, but a right that binds third parties as a real right must fit a legally recognised type and follow its formal requirements. The principle protects third parties, land-register reliability and market transparency. It is closely linked to publicity, specificity and mandatory property-law structures.