Springwell-watch: new insights into the nature of contractual estoppel

Over the last ten years, the emergence of contractual estoppel has been catalysed by litigation between sophisticated participants in the financial markets. Pending a Supreme Court decision, the principal authority remains the Court of Appeal’s 2010 decision in Springwell Navigation Corp v JP Morgan Chase Bank (‘Springwell’). It would be wrong, however, to think that the doctrine has remained static since this landmark decision, or that it has remained confined to the financial sphere, or to relationships between sophisticated parties. The paper aims to fill a gap by considering the more recent, ‘second generation’ of cases involving contractual estoppel handed down in the five years 2013-2017 inclusive, with the aims of developing our understanding of this type of estoppel and examining its actual implications to date. Overall, the paper shows how contractual estoppel has become a recurrent and predictable feature of financial markets litigation, but also how it has spread into cases involving more diverse aspects of business and personal life. It argues that this diversity matters not only because of the impact on these wide-ranging types of relationships, but also because it has influenced the development of the doctrine. In this respect, the analysis shows how existential questions about contractual estoppel have faded from the cases, to be replaced by debates about the constraints on the doctrine. As a result, having assessed the extent and implications of spread of the doctrine, the paper proceeds to analyse the status of those constraints as they currently stand, considering in turn the ‘internal’ and ‘external’ limits