Tribunal-focused changes in the ICC 2026 Rules

The 2026 ICC Rules, which came into effect on 1 June, are the most significant revision in five years, making welcome clarifications and introducing reforms to promote efficiency, flexibility and transparency during the arbitration process.

Much of the attention has focused on the removal of the previously mandatory Terms of Reference. However, among the most important modifications are tribunal-facing changes involving a revised disclosure framework, new rules on the timing of awards, and a practical clarification on truncated tribunals.

New disclosure requirements

The ICC took the opportunity with the revision of its rules to revisit one of the most basic tenets at the heart of international arbitration: the independence and impartiality of arbitrators.

The rules have long required prospective arbitrators to disclose in writing “any facts or circumstances which might be of such a nature as to call into question the arbitrator’s independence in the eyes of the parties, as well as any circumstances that could give rise to reasonable doubts as to the arbitrator’s impartiality”.

However, the 2026 revision has taken the further step of formally signalling the ICC Court’s expectation of increased transparency. Article 12(2) now requires that any doubts an arbitrator may have over whether to make a disclosure “shall be resolved in favour of disclosure”; while article 12(4) reaffirms the long-standing position that a disclosure is not, in itself, enough to establish any lack of impartiality.

The most recent Queen Mary Survey highlighted that transparency of the administrative and decision-making process, such as the selection of arbitrators, is a key factor for parties in selecting an arbitral institution. Other institutions such as the LCIA, and, most recently, SIAC have given access to challenge decisions to meet users’ demand for transparency.

Against that backdrop, the ICC Rules have broadened the opportunity for parties to become proactively involved in the disclosure process, with article 12(5) of the 2026 revisions calling for each party in a dispute to “submit to the Secretariat a list of persons and entities which they believe the prospective arbitrators and arbitrators should consider and the reasons thereof”.

The 2026 ICC Note to Parties and Arbitral Tribunals (‘the Note’) provides important operational detail. In particular, the Note clarifies that the "reasons" required under article 12(5) need only amount to a short description of the relevance of the person or entity to the dispute. The Note also makes clear that the Secretariat retains a supplementary role. Where parties are participating, the Secretariat may add to the combined list any signatories to the arbitration agreement and any affiliates of a party mentioned in the submissions and documentary evidence that the parties themselves have omitted. Where a party is not participating, the Secretariat engages more actively by endeavouring to identify relevant entities independently at the outset of the case.

This party involvement does not reduce the disclosure obligations of prospective arbitrators. Rather, the information provided by the parties will be recorded in ICC case documents, enabling them to seek clarifications as required from prospective arbitrators under ICC oversight.

The ICC’s 2026 Rules clarify and consolidate existing practice and encourage earlier and more active engagement in identifying potential conflicts – although whether this will ultimately reduce the number of unmeritorious challenges will remain to be seen.

Time limit changes

The previous 2021 Rules required that a final award must be rendered within six months from the Terms of Reference unless the ICC Court extends that deadline. In practice, however, the time limit was rarely followed, and procedural timetables in most cases would extend beyond the rules’ restrictions.

The 2026 Rules remove the fixed time limit previously prescribed in the rules. Instead, the President of the ICC Court will determine the time limit for rendering the award and may extend it by reference to the case’s procedural timetable or on a reasoned request from the tribunal. Expedited and highly expedited procedures are unaffected and continue to operate under their own specific timeframes.

The change comes as the ICC has achieved its second-highest total for approved awards in 2025, with 607 awards rendered.

Arbitral institutions are still calibrating the balance between the certainty of fixed deadlines and the flexibility needed to reflect the realities of complex cases. That tension is illustrated by Singapore’s 2025 SIAC Rules, which moved from no prescribed timeframe to a 90-day deadline for submitting awards for scrutiny from the date of the last directed oral or written submission.

The ICC’s new mechanism adopts a different and more case-specific approach, allowing timelines to be tailored to the complexity and progress of the proceedings.

Truncated tribunal

Lastly, article 16 (5) of the 2026 Rules introduces a practical clarification on truncated tribunals. It allows the ICC Court to decide that a replacement arbitrator is not required where an arbitrator has died or been removed after the last hearing or the filing of the last substantive submissions, whichever is later. Under the previous 2021 rules, that course was only available after the proceedings had closed.

This is a sensible and practical clarification furthering efficiency. Once a case has reached the stage of the last hearing or final substantive submissions, the rules now give the ICC Court greater flexibility to avoid the disruption that can follow from replacing an arbitrator at such a late stage.