The High Seas Treaty has reached more than 100 parties, after Germany, Papua New Guinea, Zimbabwe, Canada, Australia and Brunei Darussalam deposited their instruments of ratification at the UN General Assembly this week – a milestone that arrives almost exactly a year after the Treaty crossed the 60-ratification threshold needed for it to enter into force.

The Treaty officially came into force on 17 January 2026, following nearly two decades of discussion and negotiation. It delivers the world’s first comprehensive legal framework to protect ocean life across the High Seas – an area covering nearly half the planet’s surface – and offers a critical tool in addressing the interlinked crises of climate change, biodiversity loss and pollution.

With the first Conference of the Parties (COP1) scheduled for January 2027, the Treaty now enters a new phase: implementation. COP1’s priority will be agreeing the institutional setup and operating rules needed for the Treaty’s long-term success, marking a shift toward the goal it was agreed to achieve in the first place – the urgent protection of ocean life on the High Seas. 

Central to this will be establishing highly and fully protected Marine Protected Areas and setting rigorous standards for environmental impact assessments.

The Treaty’s membership already spans every region of the world – from major maritime powers to small island big ocean states, from developed to developing nations, and notably several landlocked countries – underscoring that High Seas protection is a shared global responsibility, not one confined to coastal states.

Even so, the Treaty’s legitimacy, equity and effective governance will depend on continued growth in the number and diversity of its parties. Only ratifying countries can vote and shape its decisions, meaning nations that have not yet ratified will have no seat at the table when it comes to deciding the rules for nearly half the planet.

“In many cultures, the number 100 carries real weight- whether it is a marker for age, an anniversary, or a symbol of luck and prosperity. For the High Seas Treaty, it marks the real momentum of the world uniting around ocean protection, even in divided times. But we cannot stop here,” said Rebecca Hubbard, Director of the High Seas Alliance. 

“We need more countries to ratify to achieve equitable global ocean protection by 2030. Parties need to show up ready to engage at COP1 so this wave of support turns into real decisions, not just symbolism. How countries engage in this first critical meeting will set the tone for every COP that follows, and too much is on the line to get this wrong.”

Dr. Aristide Takoukam Kamla, President and Founder of the African Marine Conservation Organization (AMCO), said: “The ratifications by African countries show that the continent intends to help shape ocean governance, not simply follow it. For coastal communities in Central and West Africa, a protected high seas means healthier fisheries, thriving marine wildlife and a more secure future.”

In Australia, Elle Lawless, Senior Ocean Campaigner at Greenpeace Australia Pacific, said: “Australia’s formal ratification of the High Seas Treaty is a historic moment we can be deeply proud of, but now we need to turn this landmark agreement into real protection for the ocean. The ocean is under mounting pressure from destructive industrial fishing, including long-lining and bottom trawling. 

“Vast, robust ocean sanctuaries offer a crucial solution, giving whales, turtles, seabirds and other ocean wildlife a safe blue haven to recover and thrive. We’re calling on the Australian government to lead with ambition, science and collaboration by championing multiple high seas ocean sanctuaries in our region, starting with a large sanctuary in the Tasman Sea between Australia and Aotearoa New Zealand.”

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