Who Controls the Ocean Floor: The Quiet Power of ISA Mining Licences

The International Seabed Authority (ISA) is the intergovernmental body that controls who can mine the international seabed — and on what terms. Understanding how ISA contracts work is essential to following the governance debates now unfolding around deep-sea mining.

What Is the ISA?

The ISA was established in 1994 when the 1982 United Nations Convention on the Law of the Sea (UNCLOS) entered into force. It is headquartered in Kingston, Jamaica, and currently has 168 member states. Its mandate is to organise and control activities in the international seabed "for the benefit of mankind as a whole," with special consideration for developing nations.

The international seabed — everything beyond the 200-nautical-mile exclusive economic zones of coastal states — is legally defined as the "common heritage of mankind." No country owns it. The ISA acts as its custodian.

Types of Contracts

The ISA issues two categories of contract:

Exploration contracts authorise a contractor to survey a defined area, collect samples, and assess the commercial viability of a deposit. They last 15 years with the possibility of extension. Contractors must submit annual reports, follow environmental regulations, and pay annual fees. Exploration does not authorise extraction.

Exploitation contracts authorise actual mining. As of 2026, no exploitation contract has been issued. The ISA's Mining Code — the regulatory framework for exploitation — remains under negotiation, delayed by unresolved disputes over environmental thresholds, royalty structures, and liability rules.

Who Holds Contracts?

Contracts are held by sponsored entities: a company or state institution that is sponsored by an ISA member state. The sponsoring state bears legal responsibility for ensuring the contractor complies with ISA regulations — creating a financial liability that has made some governments cautious.

Current contractors include:

• State entities from China, Russia, South Korea, India, France, Germany, Japan, and others
• Private companies sponsored by small island states, including the Cook Islands, Nauru, and Kiribati — which have become notable sponsors partly because of lower sponsorship costs

China holds the largest number of exploration contracts of any single state.

The Two-Year Rule and Nauru

In 2021, Nauru triggered what became known as the "two-year rule" by formally notifying the ISA of its intention to begin exploitation, compelling the ISA under UNCLOS to finalise the Mining Code within two years regardless of whether negotiations were complete. The deadline passed in July 2023 without a finalised code, creating significant legal uncertainty about whether mining could proceed anyway.

The episode exposed the tension at the heart of ISA governance: small island states with minimal environmental stake hold disproportionate procedural leverage, and the ISA's decision-making structure — requiring consensus among member states with divergent interests — is poorly equipped for the speed at which industry is pushing for commercial extraction.

Environmental Obligations

Contractors must conduct environmental baseline studies before any extraction begins, establish "preservation reference zones" left unmined for comparison, and submit environmental management plans. The ISA's environmental regulations have been criticised by scientists as underspecified — particularly regarding sediment plume modelling, the geographic scope of impact assessments, and what counts as "serious harm" to the marine environment.

Several states, including Germany, France, Chile, and New Zealand, have called for a moratorium or precautionary pause on exploitation contracts until environmental standards are strengthened.

Tracking It Yourself

Abyssal Claims provides a map of every active ISA exploration contract, including contractor name, resource type, contract area in km², and spatial overlap with hydrothermal vent fields and biodiversity hotspots. Each concession page includes ISA contract metadata and a direct link to the ISA's public contract register.