The Entire Agreement Clause: Conclusive or a Question of Weight?

This article addresses the question whether the inclusion of an entire agreement clause in an apparently complete written agreement precludes a finding that, in truth, the parties intended either a partly written and partly oral contract or a written contract and a collateral contract. According to recent decisions of the English courts, the answer is yes. However, the article discusses various reasons why the clause cannot, in principle, be conclusive. It also discusses alternative mechanisms for enforcing an oral undertaking that the evidence establishes was made and was intended to be binding, including the equitable remedy of rectification and, in contrast to English cases supporting the view that the entire agreement clause itself gives rise to a “contractual estoppel”, promissory estoppel and estoppel by convention.