A request for the prescription of provisional measures under article 290, paragraph 1, of the Convention is made in writing by a party to a dispute before the Tribunal. It may be submitted at any time during the course of the proceedings (Rules, article 89, paragraph 1).
A request for the prescription of provisional measures under article 290, paragraph 5, of the Convention may be submitted to the Tribunal (a) at any time if the parties have so agreed, or (b) at any time after two weeks from the notification to the other party of a request for provisional measures if the parties have not agreed that such measures may be prescribed by another court or tribunal.
Such request should indicate the legal grounds upon which the arbitral tribunal which is to be constituted would have jurisdiction and the urgency of the situation. A certified copy of the notification or of any document instituting the proceedings before the arbitral tribunal is also required to be annexed (Rules, article 89, paragraphs 2 and 4).
A request for provisional measures has priority over all other proceedings in accordance with article 90, paragraph 1, of the Rules.
The Chamber of Summary Procedure may be convened to carry out the functions of the Tribunal under the conditions provided for by article 91 of the Rules.
Any provisional measures prescribed or any modification or revocation thereof are forthwith notified to the parties and to such other States Parties as the Tribunal considers appropriate (Rules, article 94). Each party must also inform the Tribunal as soon as possible as to its compliance with any provisional measures prescribed by the Tribunal (Rules, article 95, paragraph 1).
When an application is made in respect of a dispute referred to in article 297 of the Convention, the Tribunal determines, at the request of the respondent or proprio motu, in accordance with article 294 of the Convention, whether the claim constitutes an abuse of legal process or whether prima facie it is well founded (Rules, article 96, paragraph 1).
A request for a determination under article 294 of the Convention must be in writing and filed within the time-limit fixed by the Tribunal. The Registrar, when transmitting a certified copy of the application, notifies the respondent of the time-limit. If the Tribunal decides proprio motu to make a determination, its decision has to be taken within two months from the date of the application (Convention, article 294; Rules, article 96, paragraphs 2 to 4).
Preliminary proceedings suspend the proceedings on the merits. Parties may submit written observations and submissions within a time-limit not exceeding 60 days. Unless the Tribunal decides otherwise, the further proceedings are oral (Rules, article 96, paragraphs 5 and 6).
The Tribunal gives its decision in the form of a judgment (Rules, article 96, paragraph 8).
Any objection to the jurisdiction of the Tribunal or to the admissibility of an application, or other objection the decision upon which is requested before any further proceedings on the merits, shall be made in writing within 90 days from the institution of proceedings (Rules, article 97, paragraph 1).
Preliminary objections suspend the proceedings on the merits. The other party may present its written observations and submissions within a time-limit not exceeding 60 days. Upon receipt of such observations and submissions, the objecting party may present its written observations and submissions in reply within a time-limit not exceeding 60 days. In principle, the further proceedings are oral (Rules, article 97, paragraphs 3 and 4).
The Tribunal gives its decision in the form of a judgment (Rules, article 97, paragraph 6).
A counter-claim must be directly connected with the subject matter of the claim of the other party and come within the jurisdiction of the Tribunal. The counter-claim is made in the counter-memorial of the party presenting it and appears as part of the submissions of that party (Rules, article 98).
(i) Request to intervene under article 31 of the Statute
A State Party to the Convention may request to be permitted to intervene if it considers that it has an interest of a legal nature which may be affected by the decision in the case (Statute, article 31; Rules, article 99, paragraph 3). The request is filed not later than 30 days after the counter-memorial becomes available unless otherwise decided by the Tribunal (Rules, article 99, paragraph 1). It must fulfil the formal requirements referred to in article 99, paragraphs 2 and 3, of the Rules.
If the request is granted, the decision of the Tribunal in respect of the dispute is binding upon the intervenor in so far as it relates to matters in respect of which it intervened (Statute, article 31).
(ii) Right to intervene under article 32 of the Statute
If a case relates to the interpretation or application of the Convention or another international agreement, the parties to the agreement concerned are notified by the Registrar and have the right to intervene in the proceedings. A declaration to that effect must be filed not later than 30 days after the counter-memorial becomes available unless otherwise decided by the Tribunal (Statute, article 32; Rules, article 100, paragraph 2). The declaration must fulfil the formal requirements referred to in article 100, paragraph 2, of the Rules.
The interpretation given by the judgment is binding upon the intervenor.
At any time before the judgment on the merits has been delivered, the parties may notify the Tribunal in writing that they have agreed to discontinue the proceedings. The discontinuance will then be recorded in an order of the Tribunal and the Registrar will be directed to remove the case from the List of cases (Rules, article 105).
Article 106 of the Rules deals with the discontinuance, at the instance of the applicant, of proceedings instituted by means of an application.