Introduction

Deep-sea mining (DSM) is the extraction of metals — notably cobalt, copper, manganese and nickel — from the seabed. Proponents argue it is needed to diversify raw materials supply, particularly for decarbonisation and the energy transition. There is no commercial-scale DSM occurring at present, though exploration activity continues in both national and international waters.

Since spring 2025, the United States has been pursuing mining permits in international waters unilaterally, bypassing the International Seabed Authority (ISA). With an unfinished ISA mining code, regulatory risk remains high. DSM proponents have increasingly shifted their narrative from supporting the energy transition towards framing DSM as a national security necessity, with reported links to the defence industry (p9).

Environmental risks Of DSM

DSM poses considerable environmental risks. The deep sea is rich in biodiversity yet one of the least explored ecosystems on the planet. Risks include physical disturbance of the seafloor, sediment plumes, accidental spills, and light and noise pollution. These impacts are expected to be extensive, severe, and last for generations (p8).

Social, economic, and cultural risks

In the Pacific, DSM could devastate fragile ecosystems, disrupt tuna spawning grounds and migratory routes, sever cultural and spiritual ties to the ocean, and reduce commercial fisheries revenues and employment (p8).

The economic viability of DSM is unproven. Companies such as Nautilus Minerals and Loke Marine Minerals have already gone bankrupt (p8), and studies indicate that if regulations required ecosystem restoration, costs would exceed any potential revenues (p8).

Opposition to DSM is growing: 970 marine science and policy experts from over 70 countries have called for a pause on DSM (p8–9), and 40 countries have announced support for a moratorium, precautionary pause, or ban (p9). Separately, 70 companies — including BMW, Google and Volkswagen — have signed a business statement in support of a moratorium (p9).

The finance sector’s commitments

The research finds that 82 financial institutions have a public policy excluding or setting conditions on DSM, have signed a relevant statement, or have otherwise expressed concern. These institutions represent approximately EUR 24 trillion in combined assets (p10).

Policy commitments to exclude DSM

Of the 82 institutions, 39 have a specific policy on DSM: 37 explicitly exclude financing, insurance or investment in DSM, and two place conditions on finance for DSM. Almost all are European, with German and French institutions leading (p10).

There is clear momentum: two-thirds of DSM exclusion policies were published in the past two years, and almost half (45%) in the past 12 months (p11). Environmental risks — particularly impacts on biodiversity and marine ecosystems — are the most commonly cited reason for exclusion, followed by economic, reputational, and regulatory concerns (p11).

Other public statements on DSM

17 financial institutions have signed the business moratorium statement, and 40 have signed a Finance for Biodiversity Foundation statement calling on governments not to proceed with DSM until environmental, social and economic risks are comprehensively understood (p12–13).

Finance sector advocacy and engagement on DSM

Some financial institutions have gone further by calling on companies to publicly disclose their exposure to deep-sea mineral extraction and to ensure responsible sourcing. Federated Hermes and Schroder Investment Management have supported shareholder resolutions on DSM at car manufacturers General Motors and Tesla (p13–14).

The path ahead

The emerging consensus within the finance sector points to a broader shift: DSM has approached the same ethical threshold as weapons, tobacco, pornography and fossil fuels (p15). Financial institutions are called on to develop and publish a clear policy not to finance, insure or invest in DSM; systematically screen for and eliminate exposure; and endorse finance industry initiatives against DSM, including by signing the business moratorium statement or the Finance for Biodiversity statement on DSM.

Governments are called on to endorse a moratorium on DSM in national and international waters, exclude DSM funding from public financial institutions, and prioritise demand-side solutions through circular economy strategies — including recycling, material substitution and reduced consumption.