AG Securities v Vaughan and Antoniades v Villiers [1988] UKHL 8 were two House of Lords cases decided in the same ruling, which together clarified and confirmed as pivotal the role of exclusive possession in identifying what constitutes a lease (including a tenancy) for the purposes of English land law.

The Court of Appeal held the reverse, but Sir George Waller dissented.

The House of Lords held that Mr Vaughan with his co-tenants were licensees only and not tenants, because none had exclusive possession and their rights could not be amalgamated to give a joint lease, while Mr Villiers and Ms Bridger did have exclusive possession of their room - albeit jointly - and therefore did have a lease, despite the wording of their agreements which identified them as having only a licence (to occupy).

[1] People could not contract out of such laws, which were intended to protect the vulnerable from harm and to prevent consent to substandard treatment by means of coercion, nor could they be avoided by choosing words that did not match the reality.

If that were possible, then sham wordings would merely become the norm, and the protective intent of the law would be unachieved: Parties to an agreement cannot contract out of the Rent Acts; if they were able to do so the Acts would be a dead letter because in a state of housing shortage a person seeking residential accommodation may agree to anything to obtain shelter...