Ricerc@Sapienza

The indispensable party rule is a procedural condition for the exercise of contentious jurisdiction by international courts and tribunals, and therefore it represents a limit of the judicial function. Its main purpose is to strike a balance between the interests of the parties to a dispute and the interests of third parties absent from the proceedings. The discretion that is implicit in the indispensable party notion explains the flexibility with which international courts and tribunals have applied it.

The author examines the ICJ judgment rendered in the case concerning Maritime Delimitation in the Indian Ocean with a two-fold objective. First, the decision is one of the rare occasions on which the Court examined a reservation to its jurisdiction based on a preexisting agreement to pursue alternative means of dispute settlement, and provides a good starting point to study one of the most common kinds of reservation to optional clause declarations.