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A form of Estoppel where one party allows another to believe that he owns land, or has an interest in land, and carry out work on the strength of that knowledge. Traditionally the courts of Equity could be petitioned to remedy such situations. In modern practice the courts have wide discretion on how to give effect to estoppel rights, but it remains uncertain whether a right that arises from proprietary estoppel is a proprietary interest in land, or a personal right. This is important, because if it is an interest in land then it is capable of binding the successor in title of the person whom the estoppel arises against. The Lra (2002) makes it clear that a proprietary estoppel can be noted on the register from the moment it arises and, if adequately noted, will bind successors in title.