The Rule in Hastings-Bass: Some Recent Developments and What November May Hold

The principle known as "the rule in Hastings-Bass" derives from the English Court of Appeal judgment of the same name in 1975. The use of the rule is, in a fiduciary context, to undo what has been done.

In practice, it is used most often where trustees have done something which has resulted in an unintended (and unanticipated) tax liability. Upon discovering the problem, the trustees seek an order from the court stating that their action was void (and therefore the tax liability does not arise). For that reason, a number of Hastings-Bass applications are opposed by Her Majesty's Revenue and Customs ("HMRC").

The rule was analysed in depth by Lloyd LJ in Sieff v. Fox [2005] EWHC 1312 (Ch), and his following statement has been held to be a comprehensive statement of the rule as it currently stands: