Pushing the envelope of proprietary interests: The nadir of the numerus clausus principle?

The numerus clausus principle is an inherent approach to the structure of property interests which is reflected in both the common and civil law and in both real and personal property. There are sound policy reasons for this approach based on economic and legal concepts. This conservative influence on property interests is increasingly being disrupted by the impact of judicial activism but more importantly by statutory property interests based upon social and environmental forces which seek to loosen the bonds of this principle. The advantages and criticisms of this principle are analysed in this article along with the potential risks of disrupting this fundamental meta-principle of property law.