The case of Amalgamated Investments v Texas Commerce Bank [1982] Q.B. 84 is actually a pretty interesting one from which law students can learn a lot. It’s all about estoppel, specifically estoppel by convention, and how it can affect legal outcomes when parties operate under a mutual assumption. The case shows how even if parties are mistaken about the underlying contractual terms, their assumptions can still create legal precedents. 

  • In the case of Amalgamated Investments v Texas Commerce Bank [1982] Q.B. 84, it was held that where parties in the course of dealing have acted upon an agreed assumption that a particular state of facts is true, both parties are regarded as estopped from questioning the truth of the assumed state of facts.

Facts of the Case Amalgamated Investments v Texas Commerce Bank

  • In 1969, C’s subsidiary borrowed money to develop an office building from D, which made the loan through their own subsidiary.
  • On 15th September, C executed a guarantee to secure all money owned by their own subsidiary to D. Despite the assumption of both parties, C did not guarantee the loans made by D’s subsidiary.
  • On 3rd May 1975, C’s subsidiary defaulted and was ordered to be wound up. D sued C for the money owed.
  • C claimed that their guarantee did not cover any money owed by C’s subsidiary to D’s subsidiary, by whom the actual loan was made.
  • D argued that they were protected by estoppel of convention-since both parties acted as though C had guaranteed the loan made by D’s subsidiary, they could not question the actual state of facts to escape liability.
  • The judge held that although D could not rely directly upon C’s guarantee, C were estopped from contending that it did not cover the loan. C appealed.

Issues in Amalgamated Investments v Texas Commerce Bank

  • Was C estopped since both parties had assumed and acted as though C had guaranteed the loan made out by D’s subsidiary?

Held by the Court of Appeal (Civil Division)

  • Finding for D, that on the facts C’s guarantee did cover the loan made by D’s subsidiary. Since the parties had acted upon the agreed assumption that C was liable for the loan, they were estopped by convention from denying their liability.

Lord Denning M.R.

  • Where parties are under a common mistake regarding the meaning or effect of a contract, that common mistake replaces the original terms of the contract on a conventional basis. From that point, the parties are to be treated as bound to that mistake, even if one party is not responsible for the mistake occurring.
  • The evidence overwhelmingly shows that when the loan was advanced to C’s subsidiary, all the parties thought that it was secured-not only by the mortgage of the building-but also by C’s guarantee.
  • In pursuing that belief, D embarked on a course of conduct-rearranging their portfolio of investments-releasing properties and monies to C-which they would not have done except on that assumed basis.
  • Now assuming that this belief was mistaken, a question arises about the law of estoppel. The mistake by D was self-induced. They had overlooked the wording of the guarantee. They thought it applied to monies owing to their subsidiary as well as monies owing to themselves equally.
  • This mistake was not induced by C. Nor did C do anything to contribute or reinforce it, except that they did not contradict it. But then how could C be expected to contradict it, when they were under the same mistake?
  • It would be clearly inequitable to allow C, in knowledge of the mistake, to take advantage of it if they had previously allowed the course of dealings to go ahead without bringing the matter to the attention of D. The fact that C was under the same mistake does not change that exploiting that mistake now would be inequitable.
  • “The doctrine of estoppel is one of the most flexible and useful in the armoury of the law. …It has evolved during the last 150 years in a sequence of separate developments…All these can now be seen to merge into one general principle shorn of limitations. When the parties to a transaction proceed on the basis of an underlying assumption-either of fact or of law-whether due to misrepresentation or mistake makes no difference-on which they have conducted the dealings between them-neither of them will be allowed to go back on that assumption when it would be unfair or unjust to allow him to do so. If one of them does seek to go back on it, the courts will give the other such remedy as the equity of the case demands” [122B].

Significance of the Case in Legal Development

Amalgamated Investments v Texas Commerce Bank has significantly influenced the application of estoppel in contractual relations:

  1. Central London Property Trust Ltd v High Trees House Ltd [1947] – Established the foundation for promissory estoppel in English law, providing a basis for the doctrines expanded in Amalgamated Investments.
  2. Baird Textile Holdings Ltd v Marks & Spencer plc [2001] – Explored the reliance aspect of estoppel, closely related to the assumptions discussed in Amalgamated Investments.
  3. Peekay Intermark Ltd v Australia and New Zealand Banking Group Ltd [2006] – Examined the misinterpretation of contract terms and its impact on party assumptions, refining the application of estoppel by convention.

Exam Questions and Answers

Below, you will find answers to questions that are most commonly asked based on this case.

How does estoppel by convention interact with other forms of estoppel, such as promissory estoppel, in contemporary UK law?

In contemporary UK law, estoppel by convention works alongside forms of estoppel like promissory estoppel to prevent parties from acting contrary to an established assumption relied upon by all parties involved. For instance, in Prime Sight Ltd v Lavarello [2013], the court considered how estoppel by convention could coexist with equitable estoppel, emphasizing the necessity of reliance and detriment for the latter.

What are the limits of reliance on mutual assumptions in contract law post-Amalgamated Investments?

Post-Amalgamated Investments, the limits of reliance are defined by the clarity of the mutual assumption and the reasonableness of the reliance. In Peekay Intermark Ltd v Australia and New Zealand Banking Group Ltd [2006], the court held that a mistaken belief or assumption must be explicitly mutual and relied upon by both parties for estoppel to apply.

How do courts determine the fairness and equity when enforcing estoppel by convention?

UK courts determine the fairness and equity in applying estoppel by convention by assessing whether it would be unjust or inequitable to allow one party to depart from the assumed facts or law upon which both parties acted. A recent example is MWB Business Exchange Centres Ltd v Rock Advertising Ltd [2016], where the court weighed the fairness of enforcing an oral agreement variation against a written contract clause prohibiting such variations.