A successful claim against the fiduciary may result in an award of compensation for loss, disgorgement of gain or restitution of property misappropriated by the fiduciary. But it will sometimes be impossible for the plaintiff to obtain complete relief, particularly if the fiduciary is insolvent or beyond the jurisdiction of the court. In some of these cases, the plaintiff may be able to pursue third parties who participated in the breach of duty. The principles governing the imposition of liability on participants are discussed in this chapter. This chapter principally examines the liability of third parties under the so-called ‘two limbs’ of Barnes v Addy. Liability under the first limb arises when the defendant has knowingly received property in breach of fiduciary duty. Liability is imposed under the second limb on a defendant who knowingly assists the commission of a breach of fiduciary duty. But, as the cases make clear, third parties can be held accountable on other equitable grounds. Finally, a common law claim can sometimes be brought in unjust enrichment against the third party which does not require proof of a breach of fiduciary duty.

Fiduciary relationships arise in equity’s exclusive jurisdiction and are relationships to which equity grants particular protection. Fiduciary obligations are owed by the fiduciary to identified others or a group of people, often described as the principal of the obligation or, somewhat confusingly, the beneficiary to whom the obligation is owed. In broad terms, the core obligation of a fiduciary is undivided loyalty. The fiduciary must act exclusively in the interests of the beneficiary. This obligation is not unbounded; for example, fiduciary obligations may be limited by time or the nature of the activities giving rise to the obligation in question. Fiduciary obligations thus exist within a defined scope. Additionally, not all of the obligations owed by the fiduciary to the beneficiary will be fiduciary obligations. For example, a trustee may be required to exercise a degree of care when making investment decisions, but this obligation is not fiduciary in nature.

Equity closely scrutinises relationships in which one party places trust and confidence in another. There are many examples of trust in human interaction, but equity cannot grant relief against every breach of trust and confidence, any more than contract law can enforce all promises. Only some trusting relationships and some obligations of confidence are protected. The relationships which equity protects are known as ‘fiduciary relationships’. A relationship of trust and confidence will be recognised as fiduciary where it arises from F (fiduciary) undertaking to act in the interests of B (beneficiary) in a matter which confers a discretion on F, and in respect of which the exercise of discretion affects B’s economic interests. B may hand over property to F, such as an investor handing over money to an investment adviser. A settlor may hand property to F to hold on trust for B. Alternatively, B may entrust F with the task of negotiating a contract on behalf of B so that F is B’s agent. Or F may be entrusted with the task of obtaining information on behalf of B which will enable B to exploit a commercial opportunity. This is also an example of agency.

This introduction traces aspects of the history of fiduciary duties in business law and scholarship. Despite fiduciary law’s centrality to business law, the chapter describes how the contractarian revolution of the 1980s contributed to the marginalization of fiduciary duties, both in theory and doctrine. However, subsequent developments, both in case law and in scholarship, have questioned some of the core assumptions of the early wave of contractarian theory. The introduction outlines three critiques that scholars have levied against the early contractarians’ view of fiduciary duties, and connects these critiques to the eighteen chapters in the volume. The introduction also provides a roadmap of our contributors’ arguments.