Introduction to proprietary estoppel

What is proprietary estoppel?

Proprietary estoppel is an equitable doctrine that prevents someone from relying in certain facts or rights which are different to earlier ones – to the detriment of someone else. This, says the law, is unconscionable behaviour. Proprietary estoppel effectively provides a means by which a person may become entitled to a proprietary right despite the absence of express intention and appropriate formalities.

A proprietary right is where a representation or assurance has been made to someone that they have acquired (or will acquire) rights in respect of land or property. The law says that it is unfair for the other party to then go back on their word where the representation or assurance has been relied upon to their detriment.

The doctrine of proprietary estoppel can therefore assist a claimant where their rights are not protected by the Law of Property Act; for instance, where an assurance in relation to the transfer of property has not been formalised in writing.

Establishing a proprietary estoppel claim

Where a claimant can prove they are entitled to property rights by way of estoppel, an appropriate remedy will be awarded. There are two main elements required to establish an estoppel claim:

Establishing an ‘equity’

The claimant must first demonstrate that circumstances have arisen which entitle them to a proprietary estoppel remedy. Three factors are required to prove proprietary estoppel:

  • An assurance: this can be an express or implied, or an active or passive assurance that the claimant has or will have rights in the property. The assurance must generally be clear and unambiguous;
  • A reliance: the claimant must demonstrate through their conduct that they relied on that assurance.
  • Change of position or detriment: the claimant must have acted to their detriment; for example, spent money on improving or buying land, or changing employment.

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For more information on:

  • Satisfying the ‘equity’
  • Scope of proprietary estoppel