The short answer: nobody owns the deep ocean floor. The longer answer is the one that matters — and it explains why the coming decade of deep-sea mineral extraction could trigger the most consequential international legal dispute since the Law of the Sea was written.
How International Seabed Law Actually Works: UNCLOS, the ISA, and the 200-Mile Line
Ocean jurisdiction operates in concentric rings from the coastline. A country controls its territorial sea (12 nautical miles), has sovereign resource rights over its Exclusive Economic Zone (200 nautical miles), and may extend seabed rights further via a continental shelf claim. Beyond those limits lies the Area — international seabed that falls under UNCLOS jurisdiction and is administered by the ISA.
The ISA issues exploration and exploitation licenses to both state-sponsored entities and private companies sponsored by member states. As of 2026, the ISA has issued 31 exploration contracts covering approximately 1.3 million square kilometers of the Pacific, Atlantic, and Indian Ocean floors — primarily targeting the cobalt- and manganese-rich polymetallic nodule fields of the Clarion-Clipperton Zone.
The US Problem: Why America Is Mining Without the Rules Everyone Else Follows
The legal status of deep-sea mineral deposits depends on where exactly they sit — and whose rules apply. Credit: Sliceisop / Pexels
The United States signed UNCLOS in 1994 but the Senate has never ratified it — making the US one of the only major economies operating outside the treaty framework. In practice, this means American companies seeking deep-sea mining rights cannot be sponsored through the ISA system. Instead, they operate under the Deep Seabed Hard Mineral Resources Act of 1980, a domestic law that predates UNCLOS and gives the US government unilateral authority to license seabed mining in international waters — a position most other nations consider legally contested.
The Trump administration has leaned into this posture. Executive orders signed in early 2026 directed federal agencies to accelerate domestic critical mineral extraction permitting, including in offshore and deep-ocean zones. Combined with the rollback of Obama-era EPA environmental protections, the practical effect is to position the US to pursue seabed extraction on its own legal terms — outside the ISA process that governs every other country.
Why the "Common Heritage" Principle Is Failing Under Commercial Pressure
The "common heritage of mankind" designation was a 1970s idealist construct — it assumed that the deep seabed's resources would be developed cooperatively, with benefits shared globally, before commercial extraction was technologically feasible. That window has closed. The technology to harvest polymetallic nodules at commercial scale now exists. The financial incentives — driven by the surging demand for cobalt, nickel, and manganese for EV batteries — are enormous. And the multilateral consensus required to enforce the ISA's authority over powerful state actors simply does not exist.
The result is a legal framework designed for a world that no longer exists, stretched over a commercial reality it was never built to handle. The ocean floor is nobody's. Which, in practice, is starting to mean it belongs to whoever gets there first with the biggest machine and the most permissive domestic law.