Arbitral confidentiality: a (mostly) private affair

"Do you expect me to talk?"

"No, Edelweiss Investments Inc, I expect you to keep the materials disclosed in the context of the Moscow arbitration confidential pursuant to the ICAC rules."

That, at least, is the response that Edelweiss Investments Inc may have been expecting from the English High Court. In the event, however, the company was ordered to provide its opponents with certain materials filed in an ongoing arbitration, to which the opponents were not a party, despite institutional rules which on their wording directed otherwise. The case serves as a useful reminder that English courts do not treat arbitral confidentiality as absolute.

The starting point under English law

It is a curious feature of English law that the confidentiality of arbitration is specifically not addressed in statute. Instead, the basic position is that the duty of confidentiality derives from an implied term of the parties' arbitration agreement. In practice, the duty is often also expressly included in such an agreement, as well as being set out in the relevant institutional rules. Parties to an English-seated arbitration (as well as the tribunal) are generally under an implied duty to maintain the confidentiality of the hearing, documents generated and disclosed during the arbitral proceedings, and the award. This is often touted as one of the key virtues of arbitration, allowing parties to resolve disputes safe in the knowledge that their intimate emails, commercial difficulties and corporate battles will be kept private.

However, the rule is not absolute. In exceptional cases, the English court may order disclosure even despite a party's countervailing duty of confidentiality.

The picture in other jurisdictions

Internationally, confidentiality is far from universal. Most famously, the United States does not recognise any automatic duty of confidentiality unless the parties expressly contract for it. In other settings, such as certain European civil‑law systems, privacy (ie closed hearings) is recognised, but confidentiality – the prohibition on sharing documents or information – is not assumed without agreement or institutional rules. There are also differences between major arbitral centres. The International Chamber of Commerce rules, for example, impose responsibilities on arbitrators, but do not always bind the parties.

For parties used to an English approach – one of the most robust default rules concerning confidentiality – it is important to be alive to the international differences.

A rare exception: Bourlakova & ors v Bourlakov & ors

The decision in Bourlakova & ors v Bourlakov & ors [2025] EWHC 3085 (Ch) is one of the rare moments where the English court recognises that the factors in favour of disclosure are sufficiently strong to justify permitting a disclosure of arbitration materials.

The dispute involved long‑running, multi‑jurisdictional proceedings. The twelfth defendant, Edelweiss Investments Inc (Edelweiss), had given an undertaking to the English court not to diminish the value of its assets except in the ordinary course of business. Shortly before Edelweiss gave that undertaking, the first and fourth claimants (the Bourlakovas) had discovered the existence of arbitral proceedings involving Edelweiss (the Arbitration). The Arbitration had been filed in the International Commercial Arbitration Court (the ICAC) in Russia by one Mr Ploshchenko, who was seeking just over USD$101m from Edelweiss.

The Bourlakovas submitted to the English court that the Arbitration may have been fraudulently instigated, representing a dishonest attempt by Mr Ploshchenko to obtain an award against Edelweiss. The Bourlakovas applied for disclosure of the statements of case and other materials in the Arbitration, on the basis that such information was necessary to ensure the effectiveness of the undertaking given by Edelweiss. Edelweiss resisted the application, arguing, amongst other things, that the court ought not to order it to break its confidentiality undertaking in the Arbitration.

The ICAC rules do impose a duty of confidentiality on the parties. However, the court held that this confidentiality was not absolute. The court – in what it stressed was an unusual case – found that there was a serious risk to Edelweiss's assets from the Arbitration. Disclosure of materials from the Arbitration was necessary to police the undertaking, and there was a further policy reason to make that order given any award from the Arbitration might benefit from enforcement under the New York Convention.

The following factors were treated as decisive in the court's discussion:

• The duty of confidentiality under the ICAC rules is not absolute. For example, Edelweiss would have been free to provide the Bourlakovas with arbitral materials if the purpose was to assist with Edelweiss's defence in the English proceedings.
• The contemplated breach of the confidentiality imposed by the ICAC rules would not be a criminal offence. English authorities on issues of confidentiality arising in a different jurisdiction generally suggest that a mere breach of foreign law will not usually be sufficient to block disclosure, and that the risk of serious consequences (ie criminal ones) is more likely to be decisive.
• The Bourlakovas offered to undertake to keep the information confidential and to only use it for limited purposes.
• The Arbitration was highly unusual – it became common ground between the parties that it was in some way 'bogus.'

The court therefore exercised its power to require disclosure of the Arbitration documents requested.

Confidentiality: what to expect from the English courts

The Bourlakova decision arose from an unusual set of facts, not least that both parties agreed that the Arbitration under consideration was in some way suspect.

The decision does, though, present a useful reminder that arbitral confidentiality is not inviolable. The English courts are willing to undertake a balancing exercise, where the duty of confidentiality is only one of the factors to be considered; and where justice requires it, arbitral documents may well be circulated more widely than parties had anticipated.

That said, arbitral confidentiality very much remains the custom in England – any party who wishes to look through it will need very specific and compelling facts, like in Bourlakova, to succeed.

This publication is a general summary of the law. It should not replace legal advice tailored to your specific circumstances.

© Farrer & Co LLP, February 2026