High Seas Treaty & Biodiversity Beyond National Jurisdiction (BBNJ)

The High Seas Alliance (HSA) sometimes uses the term “High Seas Treaty“ as a short-hand for the BBNJ Agreement. HSA acknowledges that the scope of the BBNJ Agreement encompasses all Areas beyond national jurisdiction, including the seafloor and water column. This choice of wording is intended to ease understanding for broad audiences and does not convey a prioritization among the components or principles of the BBNJ Agreement.

Track Progress & Follow Bringing the Treaty into Force with the Treaty Ratification Tracker

Conserving Marine Biodiversity: The High Seas Treaty Journey

On December 24, 2017, the UN General Assembly adopted by consensus Resolution 72/249, to convene an intergovernmental conference and undertake formal negotiations for a new international legally binding instrument (ILBI or treaty) under the UN Convention for the Law of the Sea (UNCLOS) for the conservation and sustainable development of marine biological diversity in areas beyond national jurisdiction. Resolution 72/249, with 141 government co-sponsors, sends a resounding message of support for the need to protect this neglected half of our planet.

Since 2018, States from around the world have gathered at the UN for three two-week negotiating sessions. The fourth session, originally scheduled to take place from 23 March – April 2 2020, was postponed until August 2021 and rescheduled again in March 2022 due to the COVID-19 virus. The fifth session concluded in New York in August 2022. While it did not result in the adoption of a treaty, the conference saw significant progress.

On March 4, 2023, after almost two decades of discussion, including 5 years of negotiations, the world’s governments reached agreement on key substantive issues for a new Treaty to protect High Seas marine life. The new High Seas Treaty addresses many of the governance gaps that have plagued the ocean, setting out clearer ways to conserve biodiversity in the High Seas.

In September 2025, 60 ratifications of the High Seas Treaty were achieved, triggering its entry into force on 17 January 2026 and marking a new era in ocean conservation. With the Treaty now international law, governments must turn commitments into action by advancing implementation, establishing marine protected areas, and ensuring strong environmental safeguards. The High Seas Alliance calls on all UN member states to continue ratifying the Agreement and actively support its effective delivery.

To read more about the High Seas Alliance work and PrepCom developments, visit the PrepCom Tracker website.

To see who has signed or ratified the High Seas Treaty, visit the Treaty Ratification Tracker.

Treaty Ratification Tracker

Ratification: Next Steps and Resources

Timeline

After almost two decades of discussion, including five years of negotiations from 2018 to 2023, interrupted by COVID-19, the fifth negotiating session (IGC5) concluded in New York in August 2022. While it did not result in the adoption of a treaty, the conference saw significant progress.

Following a resumed session in March 2023 and conclusion of the BBNJ agreement, the High Seas Treaty was formally adopted by UN member states in New York on June 19, 2023. In September 2025, the Treaty reached the required 60 ratifications, triggering its entry into force on 17 January 2026.

With the Treaty now international law, attention turns to governments to accelerate implementation and translate commitments into action to protect marine biodiversity in areas beyond national jurisdiction. Follow the journey toward effective delivery of this historic agreement.

Treaty Timeline

Adoption and Ratification

In June 2023, governments formally adopted the High Seas Treaty to protect ocean life. In September 2025, the Treaty reached the required 60 ratifications and officially entered into force on 17 January 2026.

With the Treaty now international law, we must ramp up international action to protect our shared ocean, mitigate climate breakdown, and safeguard the lives and livelihoods of billions of people worldwide, while encouraging more countries to join.

Follow progress on the High Seas Treaty Ratification Tracker

Ratification Tracker

Factsheet

On 4 March 2023, after 5 years of negotiations, the world reached a significant milestone for the global ocean and efforts to stem global biodiversity decline when nations agreed a new High Seas Treaty to protect ocean life. Having now been ratified by at least 60 countries and entered into force on 17 January 2026, the new Treaty provides the legal framework to address many of the governance gaps that have plagued the ocean and sets out a roadmap to conserve biodiversity in areas that lie beyond national jurisdiction.

Download the factsheet in English to find out more about the new High Seas Treaty.

Factsheet

Treaty Q&A

Watch the High Seas Treaty Briefing and download an overview of some of the key questions and answers regarding this new High Seas Treaty. Available in English I French I Spanish

Treaty Q&A

DEEP DIVES BRIEFINGS

Download and read the Deep Dives Briefings – a series of briefings that explains the key provisions of the BBNJ Agreement: