How Far Does Confidentiality Extend in English Arbitration?

A Corporation v (1) Firm B (2) Mr W [2025] EWHC 1092 (Comm)

Executive Summary

1. In the recent High Court judgment of A Corporation v Firm B and Anor, Mr Justice Foxton (Foxton J) considered the scope and limitations of arbitral confidentiality.
2. The Court took the stance that confidentiality within English arbitral proceedings extends to cover certain documents such as hearing transcripts, disclosure, arbitral awards and documents prepared for the dominant purpose of arbitral proceedings. However, a party’s documents that come into existence independent of the arbitration process will not automatically fall within the obligation of confidentiality.
3. The Court’s judgment is significant for parties and legal practitioners alike given it clarifies the boundaries of arbitral confidentiality, particularly for law firms that act for connected clients in multiple arbitrations.

Facts of the Case

The judgment concerns the Claimant’s application for interim injunctive relief against a law firm and one of its Partners (the Defendants). In short, the Defendants had acted in an arbitration between the Claimant and “Party B”, representing the interests of Party B. The law firm’s Asia office was also instructed in a separate arbitration between Party C and Party D, representing the interests of Party C. Whilst not a party to those additional proceedings, they were of relevance to the Claimant because Party D was within the same ultimate ownership of the Claimant.

The Claimant suspected that the Defendants had disclosed information relating to the first arbitration between it and Party B to the Defendant’s Asia office within the second arbitration in which it was also acting. In doing so, the Claimant alleged that the Defendants had improperly utilised confidential information arising out of one arbitration in an effort to benefit another client (Party C) in a separate arbitration. This included sharing ‘without prejudice’ settlement offers and an extract from an expert report.  

Accordingly, the Claimant sought to prevent the Defendant law firm and any of its branches from acting for Party C and for it to effectively cleanse its files of any confidential information obtained from the first arbitration.   

The Judgment

Foxton J began by acknowledging that the default rule under English law is that parties to an arbitration agreement will be taken to have agreed to an obligation of confidentiality, noting that this is essential to the privacy of arbitration. However, Foxton J went on to state that some documents are inherently more confidential or sensitive than others. Therefore, to consider the Claimant’s application, the Court had to ask two key questions:

1. what material does the obligation of arbitral confidentiality extend to; and
2. to the extent that the obligation of arbitral confidentiality is engaged, what are the relevant exceptions?

In relation to the first question, it was held that confidentiality extends to certain categories of documents and information, such as arbitration hearing transcripts, documents disclosed within the arbitration that are not already within the possession of the opponent party or parties, documents ‘generated’ or ‘prepared for’ the arbitration and arbitral awards.

However, the Court acknowledged that not all information relating to an arbitration is inherently confidential, in particular if it pertains to facts or events that predate the arbitration, or arises independently of the arbitration process. Foxton J used the example of a party buying defective goods to illustrate this, stating that the fact the party had bought the defective goods ‘does not become confidential simply because the buyer commences an arbitration against the seller’ (Judgment paragraph 18). This approach reflects the position that confidentiality in arbitral proceedings does not arise from the confidential nature of the documents but rather the private nature of arbitration itself.

The Court considered the exceptions to arbitral confidentiality and identified the following exceptions: by express or implied consent; through Court orders; necessity for protecting legitimate interests; and in the interests of justice (Judgment paragraph 27).

In considering the Claimant’s application the Court ultimately held that, although the Defendant law firm had conceded some breaches of confidence, notably the disclosure of ‘without prejudice’ offers made within the context of the first arbitration, all other alleged misuses of confidential information fell within a relevant exception or did not constitute a breach of confidentiality. It was for the Claimant to satisfy the Court that there was a real risk of confidential information passing between the relevant team and offices of the Defendant law firm and the Claimant had failed to do so.

What are the practical implications? 

The judgment is both a helpful reminder of the confidential nature of arbitral proceedings, and a warning to practitioners not to assume confidentiality by virtue of the material being used in arbitral proceedings. It clarifies the scope and limits of confidentiality in English law and offers practitioners clear examples of what will be deemed to be confidential, and what will not.

It is also important to note that this judgment is limited to the position under English law and that the position on confidentiality varies across jurisdictions. For example, whilst arbitral confidentiality is implied in English law, there is no automatic implication of confidentiality in the United States or Australia - instead parties must incorporate confidentiality through express terms in arbitration agreements, or agree to use arbitral rules that incorporate such terms.

Finally, although the Claimant’s application was ultimately rejected by the Court, the judgment is a reminder to law firms to take effective measures to protect confidential information and to put in place effective barriers to prevent the spread of confidential information when working on related cases or for related parties.