“Trillions of dollars of battery metals sitting on the ocean floor — and a UN agency, a climate deadline, and a dozen corporations fighting over who gets to pick them up.”
Executive Summary
Deep-sea mining refers to the extraction of mineral resources from the ocean floor at depths typically exceeding 200 meters, targeting three primary deposit types: polymetallic nodules (potato-sized concretions of manganese, nickel, cobalt, and copper on abyssal plains), seafloor massive sulfides (hydrothermal vent deposits rich in copper, zinc, gold, and silver), and cobalt-rich ferromanganese crusts on seamounts. The Clarion-Clipperton Zone (CCZ) in the Pacific alone is estimated to contain more nickel, cobalt, and manganese than all known land-based reserves combined — a resource endowment whose extraction could theoretically satisfy EV battery demand without the human rights, environmental, and geopolitical complications of land-based mining in the DRC, Philippines, and Indonesia. The sector entered a critical legal and commercial inflection point in 2023–2025 as the International Seabed Authority failed to finalize mining regulations on schedule and several companies pushed for provisional exploitation rights.
The Strategic Mechanism
Commercial deep-sea mining involves three sequential technical phases:
Exploration and resource assessment:
- Remotely operated vehicles and autonomous underwater systems map nodule density, grade, and seabed morphology
- 30+ exploration contracts have been issued by the ISA in the CCZ and Indian Ocean
- TOML, Metals Company (TMC), NORI, and state-backed entities from China, Russia, South Korea, and France hold major exploration areas
Extraction technology:
- Collector vehicles traverse the seabed, vacuuming nodules via hydraulic suction
- Riser systems transport slurry 4–6km vertically to surface support vessels
- Sediment plumes — the primary environmental concern — disperse laterally across vast areas, with uncertain ecological impact on poorly characterized deep-sea ecosystems
Legal framework:
- The Area (international seabed beyond national jurisdiction) is governed by the ISA under UNCLOS Part XI
- The “two-year rule” (UNCLOS Annex III): if a sponsoring state submits a mining application and the ISA has not completed regulations within two years, the applicant may proceed under interim guidelines
- Nauru invoked this provision in 2021; the ISA’s failure to complete the Mining Code by the July 2023 deadline created legal ambiguity that has not yet been resolved
Market & Policy Impact
- Critical mineral supply alternative: Deep-sea nickel and cobalt could reduce dependence on DRC (cobalt) and Indonesian/Philippines (nickel) supply chains with their associated human rights and deforestation risks
- Environmental opposition: A broad coalition of scientists, NGOs, and states (including Chile, France, Germany, New Zealand) has called for a moratorium pending environmental impact studies — generating commercial uncertainty
- China’s seabed positioning: China holds the largest exploration footprint on the international seabed of any single national entity, with state-backed COMRA managing multiple CCZ contract areas
- Automotive industry split: BMW, Google, Volvo, and Samsung SDI have stated they will not use deep-sea-mined materials in their supply chains; other manufacturers have not made equivalent commitments
- ISA governance reform: Developing nations with large EEZs are pressing to reform ISA benefit-sharing rules, potentially redirecting a larger share of any extraction revenues to the Global South
Modern Case Study: The Metals Company and the ISA Deadlock, 2023–2025
Vancouver-based The Metals Company (TMC), operating through its subsidiary NORI and sponsored by Nauru, became the focal point of the deep-sea mining regulatory crisis. After Nauru formally invoked the two-year rule in June 2021, TMC submitted the first formal commercial exploitation application to the ISA in July 2023 — the same month the ISA was supposed to have finalized mining regulations but failed to do so amid irreconcilable disagreements between pro-mining and precautionary member states. The ISA Council declined to process TMC’s application without completed regulations, and TMC faced a choice between indefinite regulatory delay and pursuing legal challenge. By 2025, no commercial deep-sea extraction had commenced, and TMC’s share price had declined dramatically from its 2021 SPAC-merger peak. China’s state entities, facing no stock market accountability pressure, continued methodical exploration activities. The episode crystallized the sector’s central paradox: the mineral volumes are enormous, the legal pathway is blocked, the environmental case is contested, and the geopolitical advantage is accruing to patient state actors over impatient commercial ones.