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, also called the High Seas Treaty, is a formal agreement that must be followed to protect and use marine life in areas not controlled by any country. It is part of the United Nations Convention on the Law of the Sea (UNCLOS). The agreement was completed during a meeting of government representatives at the United Nations on March 4, 2023, and officially accepted on June 19, 2023. To begin, the treaty needed at least 60 countries to approve it. On September 19, 2025, Morocco became the 60th country to approve the agreement, allowing it to take effect in January 2026.

In 2017, the United Nations General Assembly (UNGA) decided to hold a meeting to create a formal international agreement to protect and use marine life in areas beyond national control. This was needed because UNCLOS did not provide rules for these areas. Concerns included protecting ocean life and reducing the harm caused by overfishing to fish populations and ecosystems.

The treaty focuses on four areas: (1) marine genetic resources and their genetic data, including fair sharing of benefits; (2) area-based management tools, such as marine protected areas; (3) environmental impact assessments; and (4) helping countries build skills and share technology related to the ocean. Tools for managing areas and environmental assessments mainly aim to protect and use marine life wisely, while issues about genetic resources and sharing technology address fairness and justice.

Greenpeace described the agreement as "the biggest conservation victory ever." A major goal is the ability to create marine protected areas in international waters, which helps achieve the goal of protecting 30% of the world’s oceans by 2030. While the agreement does not directly address climate change, it helps protect ecosystems that store carbon in ocean sediments.

The High Seas Treaty has 76 sections and two additional parts. One main goal is to "protect, care for, and use the ocean responsibly in areas beyond national control for present and future generations." The agreement acknowledges traditional knowledge and includes rules about the "polluter-pays" principle, which holds those who harm the environment responsible. It also covers the effects of human activities in international waters. The agreement was accepted by all 193 United Nations member states.

Both countries and groups of countries can join the agreement. The earlier treaty, UNCLOS, was created in 1982 and started being used in 1994. As of October 2024, 170 countries are part of UNCLOS. The European Union promised financial help for the process of approving and using the new treaty.

Context

The world's oceans are losing many types of plants and animals and suffering damage to their ecosystems because of problems like climate change and human activities, such as shipping, overfishing, plastic waste, and deep-sea mining. This means there is a big need for a better system to manage the ocean, since the current system is not well connected and incomplete. It is not working well enough to protect and use marine life in areas that are not controlled by any country. The High Seas treaty tries to fix these problems by helping different groups and rules work together more effectively.

Areas outside of any country's control include the "high seas," which are the waters beyond a country's borders, and the "area," which is the deep seabed outside of any country's control. These areas cover about two-thirds of the ocean. Right now, they are managed by different rules and groups, such as organizations that manage fishing in certain regions. However, these groups can only act within their own rules, and they do not work well together. Also, these rules only cover a small part of the ocean, leaving most of it without clear rules. The other one-third of the ocean is under the control of countries, and it is called the exclusive economic zones (EEZs). These zones extend 200 nautical miles (about 370 km) from a country's coast. They are set up under an international agreement called UNCLOS, which allows countries to manage living and non-living resources in the water and on the seabed within these zones.

Some people say the name "High Seas Treaty" is not correct because it does not mention the protection of ocean life.

History

A new agreement under UNCLOS for areas beyond national jurisdiction has been discussed at the United Nations for nearly 20 years. The United Nations started preparation meetings in 2004 to create a plan for an agreement that would address problems with how these areas are governed and regulated.

On 24 December 2017, the United Nations General Assembly passed Resolution 72/249 to hold an international meeting and begin formal talks for a new legally binding agreement under UNCLOS. This agreement would focus on protecting and managing marine life in areas beyond national jurisdiction. Between 2018 and 2023, diplomats met at the United Nations Headquarters in New York City for negotiations. Five meetings have taken place so far.

The intergovernmental conference (IGC) held five sessions in 2018, 2019, 2022, and 2023 to develop the text of the legal agreement:

During the first session in September 2018, the term "Beyond National Jurisdiction" seemed to influence discussions more than the topic of biodiversity itself.

• In the second session in March and April 2019, it became clear that the idea that the new agreement "should not undermine" existing institutions could slow progress toward creating an effective agreement.
• The third session in August 2019 focused on the conflict between the principle of "freedom of the seas" and the idea that the ocean is a "common heritage of mankind."
• The fourth session was planned for 2020 but was delayed until March 2022 due to the COVID-19 pandemic. During this session, some countries did not support key parts of the agreement. However, progress was made on four main topics: marine genetic resources, sharing benefits using tools like marine protected areas, environmental impact assessments, and helping countries build capacity and transfer technology.
• The fifth session in August 2022 did not result in an agreement because of disagreements over how to share benefits from marine genetic resources and digital sequence information. The session was paused and will continue later.
• Agreement on the final text was reached on 4 March 2023 after the sixth session at the United Nations in New York. In February and March 2023, the final version was approved after nearly 20 years of work. Rena Lee, the president of the IGC, said, "the ship has reached the shore," to mark the agreement. The treaty opened for signatures in New York City on 20 September, one day after a meeting on the Sustainable Development Goals. Signatures will be accepted for two years starting 20 September 2023.

In January 2024, Ambassador Ilana Seid presented Palau’s agreement to the treaty. Palau was the first of 60 countries needed to approve the treaty for it to take effect.

The third UN Ocean Conference was held in June 2025 in Nice, France. During the conference, 19 more countries approved the treaty, increasing the total to 51. Another 20 countries signed the treaty.

On 19 September 2025, Morocco became the 60th country to approve the agreement, allowing it to take effect in January 2026.

In March 2026, Australia approved the treaty, becoming the 88th country to join. This is seen as an important step toward using the agreement.

Content of the treaty

Marine genetic resources (MGRs) are the first topic mentioned in the treaty. These resources can be used to create biochemicals for use in cosmetics, medicines, and food supplements. The economic value of these resources is not yet clear, but the possibility of profit has increased interest in exploring and using them.

During the United Nations negotiations, there was disagreement about whether the treaty should include "fish" and "fishing activities" under the rules about marine genetic resources. Some experts said that excluding fish might make it harder for the treaty to meet its goals, since fish are important for ocean ecosystems. However, the final treaty states that the rules about marine genetic resources do not apply to fish or fishing in areas beyond national borders.

The part about sharing benefits fairly and equally was also a point of debate. In the end, the treaty agreed to include both monetary and non-monetary benefits. A committee called the Access and Benefit-Sharing (ABS) committee will be created to provide guidelines for sharing benefits in a fair and transparent way.

Area-based management tools (ABMTs), such as marine protected areas (MPAs), are important for protecting and restoring ocean life. These tools can help protect certain areas beyond national borders. Marine protected areas are already in place in some regions, but they cover only a small part of the ocean. The level of protection varies, and these areas are useful for short-term actions or addressing specific issues.

To create an ABMT or MPA, a country must submit a proposal based on the best available science. The proposal will be shared publicly and reviewed by a scientific body. Stakeholders must be consulted, and the proposal must be approved by all parties or by a three-quarter majority of those voting. The decision becomes official 120 days after approval and applies to all treaty members. However, a country can opt out if it objects within 120 days.

After the treaty was finalized, some reports said it would help protect 30% of the ocean by 2030, a goal set at the UN Biodiversity Conference in 2022. Experts say the treaty can support this goal, but it will require significant action from countries.

Environmental impact assessments can help predict, reduce, and prevent harm to marine life from human activities. While these assessments are well established in areas under national control, they are less developed in international waters. Under the treaty, countries must conduct these assessments if an activity could harm the ocean or if there is not enough information about its effects.

The treaty also includes Strategic Environmental Assessments (SEAs), which look at long-term environmental impacts rather than specific activities. Countries must consider conducting SEAs for plans and programs in international waters, but they are not required to do so.

Capacity building and technology transfer focus on helping countries access research and cooperate in activities outlined in the treaty. This includes sharing information, creating guidelines, working together on ocean science, and improving national systems. Technology is important for enforcing the treaty, especially for helping developing and geographically disadvantaged countries.

A committee for capacity building and technology transfer will be created to monitor progress under the Conference of the Parties.

Institutional framework

The treaty creates a new system of organizations in Part VI, called "Institutional Arrangements." This includes the Conference of the Parties, the Scientific and Technical Body, the secretariat, and the clearing-house mechanism.

The Conference of the Parties (COP) will hold its first meeting one year after the treaty becomes active, but no later than that. At this meeting, rules for how the group will operate and how money will be managed will be created. The COP will check how well the High Seas treaty is being followed. Decisions must be made by agreement among all members. If agreement cannot be reached, a two-thirds majority of the countries present and voting will decide. The COP must also ensure transparency in how the treaty is carried out. Five years after the treaty starts, the COP will review the treaty again.

The Scientific and Technical Body will consist of members chosen by the countries and approved by the COP. These members will act as experts and work in the best interest of the treaty. Members must have knowledge from different fields. The body will give scientific advice to the COP, track and check area-based management tools, and review environmental impact assessments.

The secretariat will help the COP and its groups by providing administrative and logistical support. This includes organizing meetings and sharing information about the treaty’s progress in a timely way.

The clearing-house mechanism will be an open platform that helps share information. It will increase transparency and support international teamwork. The secretariat will manage this mechanism.

Additionally, the treaty creates several committees, including an "access and benefit-sharing committee," a "capacity-building and transfer of marine technology committee," a "finance committee on financial resources," and an "implementation and compliance committee." However, these committees are not discussed in the section about institutional arrangements.

Financial support

The European Union promised to give financial help for the process of getting official approval and carrying out the treaty.