Navigating Conflicts in High Seas Governance: Dispute Resolution Under Part IX of the BBNJ Agreement

The agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction (BBNJ Agreement) was adopted on 19 June 2023 and entered into force on 17 January 2026. Article 60 of the agreement incorporates the dispute settlement system of Part XV of the United Nations Convention on the Law of the Sea (UNCLOS). Through a technique of “deemed replication”, it also extends that system to parties that are not parties to UNCLOS. This article asks whether Part IX of the agreement (Articles 56–61) can resolve disputes arising in the regulatory space shared with the International Seabed Authority, the International Maritime Organisation, Regional Fisheries Management Organisations, and other bodies. It combines doctrinal analysis under Articles 31-32 of the Vienna Convention on the Law of Treaties, comparison with the 1995 UN Fish Stocks Agreement, and review of UNCLOS case law. On the basis of this, it argues that the weakness of Part IX lies less in the reach of the compulsory jurisdiction rather than in the absence of rules governing its interfaces with other regimes. With respect to the same, there are four challenges. First, incorporating Part XV without a “mutatis-Mutandis” formula leaves open how provisions drafted for this convention apply to BBNJ and disputes. The saving clause in Article 60(8) insulates external procedures, but provides no rule for coordinating parallel proceedings. The jurisdictional carve-out in Article 60(9-10) may remove disputes at the boundary between areas within and beyond national jurisdiction, and the replication mechanism for non-UNCLOS parties raises unresolved questions of interpretive unity. The article concludes that the most realistic response lies within the existing power of parties. This includes interpretive decision-making modalities for implementation and compliance committee cooperation arrangements with sectoral bodies and the advisory opinion procedure under Article 47(7).