Number of Arbitrators and Method of Appointment - ICSID Convention Arbitration (2022 Rules)

Parties should agree on the number of arbitrators on a Tribunal and the method of their appointment. If they cannot agree, ICSID’s default mechanism will apply (Article 37 of the ICSID Convention and Arbitration Rules 15 and 16).

The method of appointment must be established before the Secretary-General can act on an appointment made by a party.

​Party Agreement

As a first step in the appointment process, the parties should refer to the contract, treaty or law containing consent to ICSID arbitration. This instrument may include a prior agreement between the parties on the number of arbitrators and/or the method of their appointment.

Absent a prior agreement, ICSID invites the parties to agree on the number of arbitrators and the method of their appointment when ICSID registers the Request for arbitration.

A Tribunal must always consist of a sole arbitrator or any uneven number of arbitrators. The parties are otherwise free to adopt any workable method of appointment that suits their needs, including provisions on time limits and special procedures. The parties may but are not required to appoint arbitrators from the ICSID Panel of Arbitrators.

The most common agreements for three-member Tribunals are:

  • Each party appoints one co-arbitrator, and the parties agree on the third arbitrator, the President of the Tribunal. If the parties fail to agree, the Secretary-General (or the Chair of the Administrative Council) of ICSID appoints the President
  • Each party appoints one co-arbitrator, and the co-arbitrators agree on the third arbitrator, the President of the Tribunal. If the co-arbitrators fail to agree, the Secretary-General (or the Chair of the Administrative Council) of ICSID appoints the President.

Parties may agree to use a list procedure to constitute the Tribunal. List procedures can be used to appoint a sole arbitrator, the President of the Tribunal or all members of the Tribunal. Commonly used list procedures include:

  • The parties exchange a list of candidates; each party informs the other party of the candidate(s) whom it accepts or rejects
  • The parties request that ICSID provide them with a list of candidates. Each party can strike a certain number of these candidates and rank the remaining candidates. The candidate with the best ranking is appointed or, if two or more candidates have the same ranking, ICSID selects one of them
  • The parties and ICSID nominate candidates for list, and the parties are not informed which candidates were nominated by ICSID or the other party.

ICSID supports all efforts by parties to agree on the method of appointment and will follow the agreed method and facilitate the process to the fullest extent possible.

If the parties do not advise the Secretary-General of an agreement regarding the method to constitute the Tribunal within 45 days after the date of registration (Arbitration Rule 15), the Tribunal is constituted in accordance with the default mechanism in Article 37(2)(b) of the ICSID Convention.

Default Mechanism

The default formula contained in Article 37(2)(b) of the ICSID Convention and Arbitration Rule 16 provides that:

  • The Tribunal consists of three arbitrators
  • Each party appoints one co-arbitrator, and
  • The parties jointly agree on the third arbitrator, the President of the Tribunal.