ERISA grants claimants a private right of action to recover benefits due to them or to obtain “appropriate equitable relief” to enforce statutory obligations, including disclosure requirements and fiduciary duties. This civil enforcement mechanism puts teeth in the disclosure regime, as the courts have found that an incomplete or erroneous description of plan terms can sometimes bind the plan or trigger fiduciary liability. Disclosure of plan finances may deter fiduciary misconduct. Should deterrence fail, disclosure provides plan participants and beneficiaries the information they need to monitor plan administration to enforce their rights. Disclosure also gives workers the information to evaluate their employment and retirement options, allowing them to adjust their personal financial affairs to the employer’s program. Appreciating pension plan limits enables participants to determine the extent of additional individual savings needed to provide sufficient resources in retirement. Knowledge about welfare benefits assists workers making decisions about their need to save for health care costs not covered by the employer’s plan, or to secure additional life or disability insurance. This planning function promotes economic efficiency.

Non-legally binding instruments do not constitute treaties but they are widely used by states and international organisations as a form of political commitment. They have various titles, the most common of which is memorandum of understanding, although some states use this title also for treaties with a certain subject matter. In the multilateral context, non-binding instruments are often used for plans of action, guidelines and other forms of standard setting. To ensure that an instrument is non-legally binding, care must be taken in the drafting to evidence that intention, including use of the right terminology. An examination of state practice reveals broadly similar principles. Why do states and international organisations use non-legally binding instruments in preference to treaties? Reasons include confidentiality, lack of formality, and ease of amendment and termination. But there are risks, including possible lack of respect for commitments and lack of care in drafting. Non-legally binding instruments, both bilateral and multilateral instruments, may in some contexts be regarded as a form of soft law. They may also exceptionally give rise to estoppel. Non-legally binding instruments may also be evidence of a state’s decision or policy in the context of judicial review by domestic courts.

This chapter addresses the parties to international arbitration agreements. It follows the standard distinction between signatories (those persons whose names appear on the arbitration agreement – or the contract that includes an arbitration clause) and nonsignatories (those persons whose names do not appear on the arbitration agreement but are nonetheless bound by or entitled to invoke it). Part I addresses the treatment of ‘parties’ in the New York Convention and national arbitration laws governing international commercial arbitration, and the ICSID Convention governing (many) investor-State arbitrations. Part II examines the theories under which affected others – that is, nonsignatories to an international arbitration agreement – might nonetheless be bound, likewise first in international commercial arbitration and then in investor-State arbitration. Finally, Part III discusses the available empirical evidence on the parties to international commercial arbitration and investor-State arbitration proceedings.

Much equitable doctrine concerning contract law is now covered in contract law or property law subjects. Our coverage will therefore be brief. Equitable intervention into contract law takes one of four forms: (a) Equity enforces some promises which are unenforceable at common law. It may also modify or even prevent the enforcement of promises which would otherwise be enforceable at common law. These results are principally achieved by estoppel doctrines. (b) Equity sets aside contracts where the consent of a party to the contract has been impaired or vitiated by factors such as mistake, misrepresentation, undue influence or unconscionability. (c) Equity intervenes in some cases where the contract is substantively unfair; for example, where it contains a penalty clause or a clause authorising forfeiture of property. (d) Equity provides remedies unavailable at common law (or, in the case of rescission, available on restrictive conditions) which: • enforce contracts (for example, specific performance or injunctions); • set aside contracts where consent has been vitiated (rescission); • correct contracts where they do not reflect the mutual intention of the parties (rectification).

This chapter examines seven (alleged) modern fictions of private law: (i) the equitable maxim that equity treats as done that which ought to be done; (ii) estoppel; (iii) volenti non fit injuria; (iv) the single meaning rule in defamation; (v) the common intention constructive trust; (vi) remoteness in negligence; and (vii) reading down exclusion clauses. I establish whether each of these devices is a Hard Fiction, a Soft Fiction or no fiction (the Nature Classification). I classify each device in terms of the Effect Classification developed in Chapter One. If a device has been found to be a Hard or a Soft Fiction, I go on to consider whether it should be retained or abolished in favour of a specific alternative. These evaluations of individual fictions lead to general insights, which are used in the development of the Acceptance Test in Chapter Four.

Extended beyond the previous chapter’s analysis of the main problems raised by parallel proceedings, this chapter proposes a first way in which such risks can be reduced or eliminated altogether: a broader application of international res judicata. This chapter starts by defining and explaining the concept of international res judicata by comparing it to the understanding of the same concept in both civil law and common law jurisdictions. It then proceeds to argue for a broader and realistic (i.e., more flexible) application of this principle, which should be qualified as a principle of customary international law. This chapter also briefly addresses the principles of estoppel and lis pendens in international law and explains why they can be useful to answer the risks associated with parallel proceedings in the context of shareholders’ claims for reflective loss.