The High Seas Treaty entered into force in January 2026, establishing the first legal framework to protect marine biodiversity in international waters covering nearly two-thirds of Earth’s oceans.
Most of the world’s ocean is beyond any national jurisdiction. The high seas, the waters that begin where coastal nations’ exclusive economic zones end, cover around 64 percent of the ocean’s surface and about 43 percent of the entire planet. They are home to extraordinary biodiversity, from sperm whales to bioluminescent deep-sea creatures to the plankton that produce half of Earth’s oxygen. Until January 2026, they had no binding international legal protection.
The High Seas Treaty, formally known as the Agreement on Marine Biodiversity of Areas Beyond National Jurisdiction, entered into force when Morocco became the 60th country to ratify it in September 2025. The ratification threshold was crossed after nearly two decades of negotiations, making the treaty’s entry into force feel, to many of those involved, like an ending that had been almost too long awaited to be real.
The treaty creates a legal framework for establishing marine protected areas on the high seas, where currently none exist under binding international law. It establishes rules for environmental impact assessments of activities in international waters, including deep-sea mining and large-scale fishing. And it creates mechanisms for sharing the benefits of marine genetic resources, the biological material from deep-sea organisms that is increasingly sought by pharmaceutical and biotechnology companies.
The ocean does not stop at the boundaries of national waters. The species that live in it migrate across vast distances, moving between coastal zones and open ocean in ways that make their protection in national waters alone insufficient. A treaty that covers the high seas closes a gap that has existed since the first international agreements on ocean law were written.
Implementation will be the harder challenge. Monitoring and enforcing rules across 64 percent of the planet’s ocean surface, with no coastguard and no single authority, requires cooperation among all the countries that signed and ratified the agreement. The institutions created by the treaty will take time to establish and prove their effectiveness.
But the framework exists now. For the first time in human history, there is a legal basis for protecting the ocean that most of the world shares and none of it owns. The High Seas Treaty is a beginning, and beginnings matter.
Source: Ecologi