ICDPASO Commercial Arbitration Rules Interpretation Series 11

The determination of the number of arbitrators in the tribunal is a fundamental part of international commercial arbitration procedures, directly relating to the right of the parties to choose the arbitrators, the composition of the arbitral tribunal, procedural efficiency, and the fairness of the award. Article 11 of the Commercial Arbitration Rules of the International Commercial Dispute Prevention and Settlement Organization (hereinafter referred to as "ICDPASO") specifies the number of arbitrators in the tribunal, which not only respects party autonomy, but also endows the Court of Arbitration with an advisory function under specific circumstances, reflecting a balance between flexibility, certainty, and fairness. This Article consists of two paragraphs: the first paragraph stipulates that the parties' agreement prevails and allows the Court of Arbitration to propose increasing or reducing the number of arbitrators based on the specific circumstances of the case; the second paragraph establishes a default rule, stipulating that in the absence of agreement or in case of ambiguous agreement on the number of arbitrators by the parties, the Arbitral Tribunal shall be composed of three arbitrators.

I. ICDPASO Commercial Arbitration Rules Article 11 "Number of Arbitrators"

Article 11. Number of Arbitrators

1.If the parties have agreed on the number of arbitrators, such agreement shall prevail.

The Court of Arbitration may propose to the parties to increase or reduce the number of arbitrators after fully considering the complexity of the case and the amount in dispute.

2.Unless otherwise provided by these Rules, in the absence of agreement or in case of ambiguous agreement on the number of arbitrators by the parties, the Arbitral Tribunal shall be composed of three arbitrators.

II. Analysis of the Article

(1) If the parties have agreed on the number of arbitrators, such agreement shall prevail.

The Court of Arbitration may propose to the parties to increase or reduce the number of arbitrators after fully considering the complexity of the case and the amount in dispute.

1.Analysis of Core Characteristics

This paragraph establishes the principle of party autonomy: the parties' agreement on the number of arbitrators is binding and shall be respected by the Court of Arbitration. Meanwhile, the Court of Arbitration is given the power to manage the procedure and may propose to the parties to increase or reduce the number of arbitrators based on factors such as the complexity of the case and the amount in dispute. This design not only safeguards the parties' procedural autonomy but also enhances procedural flexibility through the professional judgment of the Court of Arbitration, avoiding procedural inefficiency or injustice caused by inappropriate choice of the number of arbitrators. For example, in complex cases involving high-value claims or technical expertise, the Court of Arbitration may recommend increasing the number of arbitrators to three to improve the professionalism of the award; while in cases with clear facts and small claims, it may recommend reducing the number to a sole arbitrator to save the parties' costs.

2.Comparative analysis

Compared with major international arbitration rules, this paragraph of ICDPASO Rules is consistent with mainstream practices in respecting the parties' agreement, but its feature of giving the Court of Arbitration "right to propose" rather than "right to decide" is relatively distinctive.

SIAC (Singapore International Arbitration Centre) Rules Article 19(2025)i: Allow the parties to agree on the number of arbitrators; in the absence of agreement, SIAC usually appoints a sole arbitrator, but may decide to appoint three arbitrators after considering the views of the parties. The SIAC Rules do not explicitly give the Court of Arbitration the right to propose adjusting the number of arbitrators agreed by the parties.

HKIAC (Hong Kong International Arbitration Centre) Rules Article 6(2024)ii: The parties may agree on the number of arbitrators; in the absence of agreement, HKIAC shall decide whether the case shall be referred to a sole arbitrator or to three arbitrators, taking into account the circumstances of the case. The HKIAC Rules do not stipulate that the Court of Arbitration may propose making adjustments to the parties' agreements.

ICC (International Court of Arbitration of the International Chamber of Commerce) Rules Article 12(2021)iii: The parties may agree on the number of arbitrators; in the absence of agreement, the Court of Arbitration appoints a sole arbitrator but may decide to form an arbitral tribunal with three arbitrators based on the circumstances of the case. The ICC Rules do not explicitly give the Court of Arbitration the right to propose adjusting the parties' agreement. Furthermore, the ICC Rules also stipulate that, even if the parties have agreed otherwise on the composition of the arbitral tribunal, in exceptional circumstances and to avoid a significant risk of unequal treatment and unfairness that may affect the validity of the award, the Court may appoint each member of the arbitral tribunal.

LCIA (London Court of International Arbitration) Rules Article 5(2020)iv: The parties may agree on the number of arbitrators; in the absence of agreement, the Court of Arbitration appoints a sole arbitrator unless the Court of Arbitration deems it necessary to appoint three arbitrators. The LCIA Rules do not stipulate that the Court of Arbitration may propose adjusting the parties' agreement.

SCC (Stockholm Chamber of Commerce Arbitration Institute) Rules Article 16(2023)v: The parties may agree on the number of arbitrators; in the absence of agreement, the Board shall decide whether the tribunal shall consist of one or three arbitrators, having regard to the complexity of the case, the amount in dispute and other relevant circumstances. The SCC Rules do not involve the right to propose adjusting the parties' agreement.

ICDPASO Rules, on the basis of the parties' agreement, introduce the Court of Arbitration's right to propose rather than right to decision, reflecting a relatively restrained degree of procedural intervention. It aims to optimize the choice of the number of arbitrators through the professional judgement of the Court of Arbitration, rather than by leveraging the Court's decision-making power when the parties have not reached an agreement.

3.Jurisprudence analysis

The jurisprudential basis of this paragraph derives from two core principles. On the one hand, the principle of party autonomy, as the cornerstone of arbitration, entitles the parties to independently design the procedure, including the choice of the number of arbitrators. This reflects the contractual nature of arbitration and respects the parties' commercial judgment and risk preferences. On the other hand, the principle of balancing procedural efficiency and fairness: the Court of Arbitration's proposal right is a reasonable supplement to party autonomy, preventing the parties from making impractical choices about the number of arbitrators due to information asymmetry or lack of experience. This design is in line with the development trend of "managed arbitration" in international commercial arbitration, emphasizing the positive role of arbitration institutions in procedural optimization.

This provision also reflects the restraint of institutional discretion. The "right to propose" rather than "right to decide" of the Court of Arbitration under the ICDPASO Rules reflects respect for the parties' independent choices and avoids excessive institutional intervention, which is more in line with the party-centered trend of modern arbitration.

(2) Unless otherwise provided by these Rules, in the absence of agreement or in case of ambiguous agreement on the number of arbitrators by the parties, the Arbitral Tribunal shall be composed of three arbitrators

1. Analysis of Core Characteristics

This paragraph establishes a default rule for cases in the absence of agreement or in case of ambiguous agreement on the number of arbitrators by the parties: the Arbitral Tribunal shall be composed of three arbitrators, unless otherwise provided by these Rules. This default rule provides procedural certainty and avoids delays or disputes caused by undetermined number of arbitrators. Meanwhile, the expression "unless otherwise provided by these Rules" leaves room for flexibility in special circumstances (such as the Expedited Procedure or Emergency Arbitrator Procedure under the ICDPASO Rules).

2.Comparative analysis

The default rule of three arbitrators in this paragraph differs from many institutional rules:

SIAC Rules (Article 19): In the event that the parties have not agreed on the number of arbitrators, a sole arbitrator shall be appointed unless the Registrar determines the dispute warrants three arbitrators after considering the views of the parties.

HKIAC Rules (Article 6): In the absence of an agreement, HKIAC shall decide whether the case shall be referred to a sole arbitrator or to three arbitrators, taking into account the circumstances of the case.

ICC Rules (Article 12): Where the parties have not agreed upon the number of arbitrators, the Court shall appoint a sole arbitrator.

LCIA Rules (Article 5): In the absence of an agreement, a sole arbitrator is appointed by default.

SCC Rules (Article 16): Where the parties have not agreed on the number of arbitrators, the Board shall decide whether the Arbitral Tribunal shall consist of a sole arbitrator or three arbitrators, having regard to the complexity of the case, the amount in dispute and any other relevant circumstances.

The ICDPASO rules introduce the arbitration institution's power of recommendation rather than decision-making on the basis of party agreement. This aims to optimize the selection of the number of arbitrators through the institution's professional assessment, highlighting the value orientation of enhancing dispute resolution services. This design also indirectly demonstrates that the ICDPASO arbitration rules do not rely solely on a single criterion to determine the number of arbitrators. Their institutional flexibility is highly compatible with the diverse nature of international commercial disputes.

3.Jurisprudence analysis

Firstly, the principle of procedural certainty and predictability: the default rule eliminates ambiguity when the parties have no agreement, ensuring the rapid formation of the arbitral tribunal, which is in line with the efficiency value of arbitration.

Secondly, the value orientation of fairness over efficiency: three arbitrators can usually provide a more comprehensive perspective, more professional judgment, and better checks and balances. Especially in international commercial disputes, it helps to enhance the authority and enforceability of the award. This choice reflects ICDPASO's pursuit of high-quality dispute resolution.

Finally, the flexibility of exception clauses: "unless otherwise provided by these Rules" reflects the internal coordination of the rule system, allowing the default rule to be superseded in cases such as summary procedures and small-value disputes to achieve the balance of efficiency and fairness.

III. Analysis of Applicability of the New Arbitration Law of the People's Republic of China

The newly revised Arbitration Law of the People's Republic of China (revised at the 17th meeting of the Standing Committee of the 14th National People's Congress on September 12, 2025, hereinafter referred to as the "New Arbitration Law") further aligns with international practices in terms of the number of arbitrators, strengthening party autonomy and procedural flexibility. Its relevant provisions are highly compatible with Article 11 of the ICDPASO Rules:

(1) Unity of the Principle of Party Autonomy

Article 43 of the New Arbitration Law stipulates: "If the parties agree that the arbitration tribunal shall be composed of three arbitrators... If the parties agree that the arbitration tribunal shall be composed of one arbitrator...". This article regulates both the number of arbitrators and the composition of the arbitration tribunal, the same as ICDPASO Rules placing the parties' agreement in the first place, reflecting the principle of party autonomy, which is at the core of international commercial arbitration.

(2) Coordination of the Number of Arbitrators

Article 42 of the New Arbitration Law stipulates: "An arbitration tribunal may be composed of either three arbitrators or one arbitrator. An arbitration tribunal composed of three arbitrators shall have a presiding arbitrator." Both this provision and the ICDPASO Arbitration Rules endow institutions with a certain degree of discretion at the rule design level and complement one another in procedural management. In practice, the connection can be realized through the proposal function of the ICDPASO Court of Arbitration.

(3) Differentiation and Complementarity of Default Rules

The New Arbitration Law does not explicitly stipulate the default number of arbitrators, while the ICDPASO Arbitration Rules take three arbitrators as the default, providing clear expectations for the parties. This difference can form a positive interaction in practice. When participating in ICDPASO arbitration proceedings, the parties can rely on its default rules to avoid procedural stagnation caused by ambiguous agreements, while enjoying the flexibility granted by the New Arbitration Law.

IV. Conclusion

Article 11 of the ICDPASO Arbitration Rules constructs a flexible and stable mechanism for determining the number of arbitrators by integrating party autonomy and professional proposals from the Court of Arbitration. With a three-tiered structure of "party autonomy + institutional restrained proposal + three-arbitrator default", it creates a flexible space between respecting commercial arrangements and ensuring the quality of awards. It demonstrates a high degree of compatibility with China's New Arbitration Law and provides an adaptive rule for international commercial market participants to balance efficiency and fairness in arbitration practice.

i.SIAC Rules art. 19(2025), which provides that: "19.1 Unless otherwise agreed by the parties, the Tribunal shall comprise one or three arbitrators. In the event that the parties have not agreed on the number of arbitrators, a sole arbitrator shall be appointed unless the Registrar determines, after considering the views of the parties, that the dispute warrants the appointment of three arbitrators."

ii.HKIAC Rules art. 6(2024), which provides that: "Article 6 – Number of Arbitrators 6.1 If the parties have not agreed upon the number of arbitrators before the arbitration commences or within 30 days from the date the Notice of Arbitration is received by the Respondent, HKIAC shall decide whether the case shall be referred to a sole arbitrator or to three arbitrators, taking into account the circumstances of the case. 6.2 Where a case is conducted under an Expedited Procedure in accordance with Article 42, the provisions of Article 42.2(a) and (b) shall apply."

iii.ICC Arbitration Rules art. 12(2021), which provides that: "Article 12 Constitution of the Arbitral Tribunal - Number of Arbitrators 1) The disputes shall be decided by a sole arbitrator or by three arbitrators. 2) Where the parties have not agreed upon the number of arbitrators, the Court shall appoint a sole arbitrator, save where it appears to the Court that the dispute is such as to warrant the appointment of three arbitrators. In such case, the claimant shall nominate an arbitrator within 15 days from receipt of the notification of the decision of the Court, and the respondent shall nominate an arbitrator within 15 days from receipt of the notification of the nomination made by the claimant. If a party fails to nominate an arbitrator, the appointment shall be made by the Court. 9) Notwithstanding any agreement by the parties on the method of constitution of the arbitral tribunal, in exceptional circumstances the Court may appoint each member of the arbitral tribunal to avoid a significant risk of unequal treatment and unfairness that may affect the validity of the award."

iv.LCIA Rules art. 5(2020), which provides that: "Article 5.8 A sole arbitrator shall be appointed unless the parties have agreed in writing otherwise or the LCIA Court determines that in the circumstances a three-member tribunal is appropriate (or, exceptionally, more than three)."

v.SCC Rules art. 16(2023), which provides that: "Article 16 Number of arbitrators(1) The parties may agree on the number of arbitrators.(2) Where the parties have not agreed on the number of arbitrators, the Board shall decide whether the Arbitral Tribunal shall consist of a sole arbitrator or three arbitrators, having regard to the complexity of the case, the amount in dispute and any other relevant circumstances."