Potential and pitfalls of the advisory function of ITLOS under the BBNJ Agreement

Abstract The BBNJ Agreement aims to regulate conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction, including through the establishment of area-based management tools (ABMTs) such as marine protected areas. One of the BBNJ Agreement’s institutional innovations is Article 47(7), which contains a novel mechanism allowing the Conference of the Parties (CoP) to request advisory opinions from the International Tribunal for the Law of the Sea (ITLOS) on the conformity of proposals with the BBNJ Agreement. This article offers an in-depth analysis of this mechanism. It examines the advisory opinion mechanism with a particular focus on the applicable procedural framework, the scope of advisory jurisdiction of the Tribunal and the function and potential of the advisory opinion mechanism in contributing to the legality, legitimacy, and effectiveness of decision-making regarding ABMTs under Part III of the BBNJ Agreement. The article revisits ITLOS’s full-bench advisory jurisdiction, including the contested question of its legal basis. Next, the article examines how Article 47(7) BBNJ Agreement operationalizes this mechanism and outlines key procedural aspects. Thereafter, the article analyses the prerequisites for, and limits to, the Tribunal’s advisory jurisdiction under Article 47(7) BBNJ Agreement, before turning to the legal significance of advisory opinions rendered under this mechanism. The article concludes that while the advisory function of the Tribunal may enhance the legal certainty, legitimacy, and effectiveness of CoP decision-making – particularly in contested or institutionally complex ABMT contexts – its potential is curtailed by a narrow jurisdictional mandate and additional limitations to subject-matter jurisdiction.