Centrovincial Estates plc v Merchant Investors Assurance Company Ltd [1983] is a foundational authority for the objective theory of agreement, establishing that a binding contract is formed through an unambiguous offer and acceptance regardless of a party’s subjective mistake, provided that error was not known to the offeree.

Facts of the Case

The plaintiffs (landlords) let premises to the defendants (tenants) under a lease that included a rent review clause. In June 1982, the plaintiffs’ solicitors sent a formal letter inviting the defendants to agree to a new “current market rental value” of £65,000. The defendants’ company secretary replied the next day, formally agreeing to this figure.

Upon receiving the acceptance, the plaintiffs immediately telephoned and wrote to the defendants, explaining that the £65,000 figure was an error: they had actually intended to propose a rent of £126,000. The defendants refused to accept the corrected terms, insisting that a binding agreement had already been concluded at £65,000.

Legal Issues

The primary issue was whether a party can resile from an unambiguous offer that has been unequivocally accepted if that offer contained a material mistake. The court also had to consider if the objective principle was based on estoppel — meaning the agreement would only be binding if the offeree had altered their position or acted to their detriment in reliance on the offer.

Judgement

The Court of Appeal ruled in favour of the defendants, giving them unconditional leave to defend the action. The court held that:

  • An offer must be interpreted objectively, based on how a reasonable person in the shoes of the offeree would understand it, rather than by the subjective intent of the offeror.
  • Once an offer is unequivocally accepted, a legally binding agreement is formed that cannot be revoked without mutual consent.
  • The plaintiffs could only escape the contract if they could prove at trial that the defendants actually knew, or ought reasonably to have known, that the offer contained an error at the time they accepted it.

Authority and Significance

This case is a landmark illustration of the objective approach in English contract law. Its significance includes:

  • Objective interpretation: it confirms that the “meeting of minds” (consensus ad idem) required for a contract is determined by outward manifestations — words and conduct — rather than inner thoughts.
  • Rejection of estoppel basis: the court explicitly rejected the argument that the objective rule depends on estoppel. A contract becomes binding the moment of acceptance, even if the offeree has not yet relied on the promise or changed their position to their detriment.
  • Commercial certainty: the ruling promotes security in commercial transactions; if parties could escape agreements by simply asserting a private mistake, the reliability of business dealings would be significantly undermined.

The “snapping up” boundary: it reinforces that while an objective agreement is generally binding, a party cannot “snap up” an offer they know to be a mistake — though the burden of proving such knowledge lies with the mistaken party.