act of notoriety", or "solemn formal act”) is the historical root of common law estoppel by representation and equitable estoppel. Estoppel in pais and equitable estoppel are used interchangeably in American legal parlance. Estoppel by convention as understood in English law (also known as estoppel by agreement) occurs where two parties negotiates or operates a contract based on a shared assumption or mutual understanding of a legal effect (or interpretation) of that contract, they are bound by that belief, assumption or understanding if (i) they both knew the other operated under the same, and (ii) they both regulated their subsequent dealings on the same. It has been said that estoppel by convention is not truly an estoppel but merely an instance of estoppel by representation, promissory estoppel or proprietary estoppel, though the first of the three is its most frequent manifestation. Estoppel by deed is a rule of evidence. A statement in a deed, usually facts stated in the recital of a deed, is evidentially conclusive against the parties of the deed. The parties are estopped from asserting otherwise. See also Consideration in English law References Bibliography Further reading David Swarbrick. Estoppel (England) – 1980- 1984, website of swarb.co.uk "Estoppel, in its various forms including proprietary and equitable estoppels". Estoppel English contract law Equitable defenses English legal terminology