Filling Gaps in UNCLOS: The New High Seas Treaty

One of the most comprehensive frameworks in international law, the United Nations Convention on the Law of the Sea (UNCLOS), has recently been strengthened through the ratification of a new treaty: 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). Adopted by UN member states in 2023, the treaty obtained the required 60 ratifications in September 2025, passing the threshold for entry into force and set to take effect in January 2026.

Having been negotiated for nearly two decades, this agreement builds on UNCLOS and fills a gap in international law by establishing precedents for biodiversity governance in marine areas beyond national jurisdiction, which are collectively referred to as the ‘high seas.’

With the high seas being historically subject to pollution, overfishing, and other environmental hazards, the new BBNJ  treaty has been described as a “lifeline for the ocean” by Susain Gardner, the Director of the Ecosystems Division at the United Nations Environment Programme (UNEP). The treaty makes strides towards safeguarding ecosystems and promoting the sustainable use of marine biological resources, particularly with regard to the provisions of the Convention on Biological Diversity (CBD). This article unpacks some of the BBNJ’s key provisions.

One of the key elements of the Agreement is its effort to manage marine genetic resources (MGR) in a sustainable and equitable matter. MGR play a vital role in producing enzymes, cosmetics, and medication used in everyday life, such as antiviral and antimicrobial agents. The BBNJ established a Marine Genetic Resources mechanism to uphold the principle of access and benefit sharing for managing the lucrative natural resources present in the high seas. Access and benefit sharing is a major foundation of legal frameworks that govern biological diversity. As outlined in the Nagoya Protocol, the principle governs how genetic resources are accessed and how their monetary and non-monetary benefits are shared equitably. 

Access and benefit sharing is reflected in the BBNJ through its requirement that states must share non-monetary benefits by providing access to samples and digital sequence information. States must ensure that any gathered information on marine genetic resources beyond national jurisdiction is reported to a Clearing-House mechanism, which serves as an open-access platform for sharing data and information. Reports must be made before and after MGR collection or sampling, and at the stage of utilisation and commercialisation.

In terms of sharing monetary benefits, the Agreement stipulates that payments will be made to a special fund which will be used to assist developing State Parties with implementing the BBNJ. These access and benefit sharing measures will help to ensure that developing states are not left behind, and that no states gain a monopoly on reaping the monetary and non-monetary benefits of MGR collection and use in areas beyond national jurisdiction.

The Agreement also emphasises the importance of capacity building and the transfer of marine technology as a means to support developing states. Specific examples of capacity building include strengthening relevant infrastructure and financial management systems, sharing manuals, and developing scientific research programmes. The BBNJ requires Parties to provide resources for the development of marine technology to developing states within their capabilities. A funding mechanism is also created to support these activities. The treaty sets about monitoring these efforts by establishing a special committee for the purpose of measuring performance and reviewing capacity-building efforts. These provisions will help to create more equal footing for states with different capabilities.

The BBNJ also deserves recognition for its effort to strive for more inclusive environmental governance, aiming to foster collaboration with Indigenous Peoples and local communities (IPLCs). The BBNJ affirms the need to integrate knowledge from IPLCs into biodiversity management. Article 7 outlines the use of traditional knowledge possessed by IPLC as a guiding principle for achieving the treaty’s objectives. Article 52 states that funding will be used to support conservation programmes promoted by IPLCs.

This priority also aligns with other recent efforts made by the UN to incorporate IPLCs into environmental frameworks, such as the establishment of a permanent body on IPLCs’ contribution to biodiversity stewardship. The subsidiary body, known as the Subsidiary Body on Article 8(j) and Related Provisions of the Convention on Biological Diversity, or the SB8J, advises the Conference of the Parties (COP) on matters relating to traditional knowledge and community protections, promotes respect for cultural heritage, and supports capacity-building between IPLCS and scientific institutions. By allocating funding to such capacity-building, the BBNJ creates a firm precedent of continued collaboration with IPLCs and incorporation of traditional knowledge. In doing so, the BBNJ also supports Goal C of the Kunming-Montreal Global Biodiversity Framework. In sum, BBNJ not only endeavours to maintain the principle of benefit sharing across communities, but also seeks to ensure that IPLCs are consulted with and integrated into conservation plans.

The BBNJ makes yet another elaboration on UNCLOS by establishing thresholds and detailed processes for conducting and reporting environmental impact assessments. Parties must conduct an environmental impact assessment under their jurisdiction to evaluate potential harm that may be caused as a result of an activity that will take place in the high seas, including large-scale commercial activities.

The state with jurisdiction over the activity then makes a decision on whether or not an activity can proceed, but other states can still register concern over an authorised activity by reporting it to the Scientific and Technical Body established by the treaty. These provisions will influence how activities such as seabed mining are conducted by requiring activities to comply with tight regulations, which can be effective for preventing damage to ecosystems. This effort to mitigate environmental harm is especially pertinent, with nearly 10% of marine species at risk of extinction according to estimates from the International Union for Conservation of Nature.

Conclusion 

The BBNJ is an impressive feat of international law that strengthens governance of biological diversity in the high seas by establishing detailed frameworks for conservation and sustainable use, provisions which had been previously unspecified by UNCLOS. The binding nature of the BBNJ is designed to help the international community to reach environmental targets, especially under the Kunming-Montreal Global Biodiversity Framework, which aims for 30% of sea areas to be protected by 2030. Long-overdue frameworks for protecting valuable biodiversity in the high seas will now become enshrined into international law, creating hope for the future of inclusive environmental stewardship.

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