Keech v Sandford [1726] EWHC J76 is a foundational case, deriving from English trusts law, on the fiduciary duty of loyalty.

[1] Keech reversed this, and the law in England and the UK has maintained a strict opposition to any possibility of a conflict of interest ever since.

[2] The remedy of granting a constructive trust over property, and the strict approach that all possibility of a conflict of interest was to be avoided, derived from the general outrage at the time.

A person being possessed of a lease of … a market, devised his estate to trustee in trust for the infant; before the expiration of the term the trustee applied to the lessor for a renewal for the benefit of the infant, which he refused, … there was clear proof of the refusal to renew for the benefit of the infant, on which the trustee sets a lease made to himself.The Lord Chancellor, Lord King ordered Mr Sandford should disgorge his profits.

Strict duties for trustees made their way into company law and were applied to directors and chief executive officers.