What is meant by ‘“proprietary”?

In a strict sense, a “proprietary interest” means an advantage, profit, right or share held by the owner of a tangible of intangible asset or property with all the rights associated with it. In this context it refers to the prior rights held by Māori over freshwater bodies which the Crown has consistently ignored (or extinguished) over time. A proprietary interest may be weak or strong, from outright unfettered control of an asset to a restricted right to use an asset.