Is proprietary estoppel a sub-species of promissory estoppel? Must the claimant believe that the assurance received is legally binding on the defendant for detrimental reliance to be reasonable? The House of Lords’ decision in Yeoman’s Row Management Ltd v. Cobbe 1 controversially suggested that both questions should be answered in the affirmative, fuelling fears that the doctrine was effectively “dead”.2 Less than a year later, its decision

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