In the seventeen months since President Trump’s April 2025 executive order directing United States agencies to accelerate deep-sea mining permitting in both U.S. and international waters, the legal landscape has shifted dramatically. This update surveys (I) the key domestic regulatory developments, (II) the legal risks confronting companies pursuing mining under U.S. authority, and (III) the evolving international legal framework.

I. Developments in the U.S.

The U.S. has pursued deep-sea mining on two tracks: leasing areas of the U.S. outer continental shelf for critical mineral development and creating a new pathway for U.S. companies to obtain permits for commercial recovery of minerals from the seabed beyond national jurisdiction.

The Bureau of Ocean Energy Management (BOEM), which became the Marine Minerals Administration (MMA) in July 2026, has moved aggressively to lease deep-sea minerals on the U.S. Outer Continental Shelf (OCS). To date, the MMA has targeted four regions of the U.S. OCS:

On January 21, 2026, NOAA published a final rule revising regulations issued in 1981 and 1989 under the Deep Seabed Hard Mineral Resources Act (DSHMRA) governing exploration, licensing and commercial recovery of minerals on the seabed beyond national jurisdiction. The DSHMRA is a 1980 United States federal law that governs the exploration and commercial recovery of deep-sea minerals by U.S. citizens and companies in areas beyond national jurisdiction. It was meant to be an interim framework during the negotiation of the UN Convention on the Law of the Sea (UNCLOS).

The January 2026 final rule is notable in two principal respects. First, it establishes a consolidated application process under which an eligible applicant may apply for an exploration license and a commercial recovery permit simultaneously. Second, the rule formally asserts authority under DSHMRA to issue exploration licenses and commercial recovery permits for the seabed beyond national jurisdiction. Unilateral U.S. mining has been controversial because it undermines the International Seabed Authority (ISA)’s exclusive jurisdiction over the seafloor beyond national jurisdiction and, in so doing, arguably violates customary international law, as described further in Section II(B) below.

NOAA framed the rule as giving effect to the Trump Administration’s “America First” agenda by enabling access to resources for U.S. companies vis-à-vis non-U.S. companies and increasing economic resilience through increased access to critical minerals. Only a U.S. citizen, whether an individual or a corporation, can be authorized to mine under the DSHMRA. NOAA responded to and rejected public comments arguing that the rule violates the National Environmental Policy Act (NEPA). NEPA requires environmental review of major federal actions, and commenters argued that the promulgation of these regulations is itself a major federal action requiring environmental review.

NOAA also responded to and denied arguments that the rule would be contrary to Indigenous values and go against NOAA’s responsibilities to Indigenous peoples under executive orders on Indigenous consultation.

The day after NOAA published the rule, The Metals Company USA (TMC USA)—a subsidiary of The Metals Company (TMC), incorporated in Canada—submitted the first consolidated application under the revised process. TMC expanded its proposed commercial recovery area from approximately 25,000 to 65,000 square kilometers in the Clarion-Clipperton Zone (CCZ), an area on the Pacific Ocean seabed beyond national jurisdiction rich in polymetallic nodules. Portions of the area that is the subject of TMC USA’s application overlap with areas for which TMC’s Naoero- and Tonga-based subsidiaries have exploration contracts with the ISA. In May 2026, NOAA determined that TMC USA’s application was in full compliance with the DSHMRA requirements, advancing it to the next stage of review. TMC USA stated that it expects the permitting process to be complete by the first quarter of 2027.

Other companies—SeaX, Inc., American Metal Resources, and American Deep Sea Minerals—have also submitted applications for exploration licenses in the CCZ, and a total of nine companies are reported to be in talks with the Trump Administration.

II. Legal Risks of Deep-Sea Mining Unilaterally Authorized by the U.S.

While the U.S. unilateral permitting pathway may be moving more quickly than the negotiations under the auspices of the International Seabed Authority for regulations governing commercial recovery of minerals from the seabed beyond national jurisdiction, it is not without its risks. Industry members involved in deep-sea mining under U.S. authority face nontrivial legal risks under U.S. domestic law and international law as implemented through other nations’ domestic laws.

A. Legal Risks Under U.S. Statutes

The DSHMRA creates several avenues litigants could pursue to reshape, slow, or block deep-sea mining projects. Further, operating under U.S. jurisdiction means that the full suite of U.S. environmental laws applies to mining activities, opening multiple avenues for legal challenge.

(1) The DSHMRA contains a private right of action under 30 U.S.C. § 1427. This provision authorizes “any person” with a “valid legal interest which is or may be adversely affected” to begin a civil action for equitable relief in the U.S. District Court for the District of Columbia. It enables suits against both the NOAA Administrator for failure to perform non-discretionary duties and against permit holders for violations of the Act or permit conditions.

A challenger could use this provision to enforce the substantive conditions the DSHMRA places on issuing permits. For example, under 30 U.S.C. § 1415, NOAA may not approve an application if the proposed activity is “reasonably expected to result in a significant adverse effect on the quality of the environment.” NOAA also may not approve an application that would “unreasonably interfere with the exercise of the freedoms of the high seas by other states” or would conflict with “any treaty or international convention in force with respect to the United States.” A challenger could argue that the scientific evidence compiled to date demonstrates that deep-sea mining would cause significant adverse environmental effects. Alternatively, a challenger could argue that the environmental harm would interfere with fishing. Fishing is one of the recognized freedoms of the high seas in customary international law applicable to the United States. The DSHMRA also requires NOAA to use the “best available technologies for the protection of safety, health, and the environment” when issuing new permits, creating another basis for challenge if NOAA fails to enforce the standard.

(2) Deep-sea miners and other industry participants could face hurdles in the permitting process as a result of the permitting agencies’ risk of suit under the National Environmental Policy Act (NEPA). The DSHMRA expressly provides that the issuance of any license or permit “shall be deemed to be a major Federal action significantly affecting the quality of the human environment” for NEPA purposes. Industry participants would need to take part in the agency-led, time-intensive NEPA review process before issuance of a permit, or risk litigation. An NGO could challenge any environmental impact statement as failing to take a “hard look” at environmental consequences, failing to consider a reasonable range of alternatives, or omitting analysis of cumulative impacts. Notably, Environmental Defense Fund, Inc. v. Massey (1993) holds that NEPA applies in Antarctica because the U.S. has “legislative control” over activities there. The court compared Antarctica to the high seas, bolstering the argument that NEPA review must be completed for any deep-seabed mining under U.S. jurisdiction.

Foreign governments may also be able to sue under NEPA. NEPA has no cause of action of its own, so NEPA challenges are brought under the Administrative Procedure Act (APA), which allows suit by a “person . . . adversely affected or aggrieved by agency action.” See 5 U.S.C. §§ 551(2), 701(b)(2), 702. Courts have read the APA’s definition of “person” to reach foreign governments and their agencies in the Freedom of Information Act context. See Stone v. Export-Import Bank, 552 F.2d 132, 136–37 (5th Cir. 1977) (holding that a Soviet government agency is a “person” under FOIA Exemption 4 because nothing in § 551(2) limits the term to American entities); Neal-Cooper Grain Co. v. Kissinger, 385 F. Supp. 769, 776 (D.D.C. 1974) (concluding that a foreign government “would appear to be a ‘public or private organization’” under § 551(2) and thus a “person” entitled to request records); Md. Dep’t of Human Res. v. Dep’t of Health & Human Servs., 763 F.2d 1441, 1445 n.1 (D.C. Cir. 1985) (relying on those decisions to hold that a U.S. state is an APA “person”).

Foreign litigants have used this path in practice. In Government of the Province of Manitoba v. Norton, a Canadian province challenged a federally funded water project under NEPA and obtained a remand of the environmental assessment. 398 F. Supp. 2d 41, 44–45, 65–66 (D.D.C. 2005). A coastal nation could likewise allege that sediment plumes or disrupted fish stocks from a licensed area would migrate into its waters and injure resources it owns or manages, and then raise the same claims available to an NGO.

(3) Deep-sea mining industry participants would also need to comply with the Marine Mammal Protection Act (MMPA). The MMPA expressly prohibits the “taking” of marine mammals in U.S. waters and by U.S. citizens on the high seas. It likely applies to the impacts that deep-sea mining would have on marine mammals in the waters above mining sites. Industry participants would need to ensure they comply with the MMPA or risk enforcement actions through NOAA and lawsuits brought by impact litigation groups seeking to ensure the law is followed.

(4) The Endangered Species Act (ESA) applies to any person subject to the jurisdiction of the United States and makes it illegal to “take” listed species, including on the high seas. Deep-sea mining industry participants would face risk of suit for impacts to federally listed species.

U.S. environmental nonprofits have already indicated a willingness to bring suit and are watching the space closely. On September 30, 2026, the Center for Biological Diversity and the Conservation Council for Hawai’i filed suit against NOAA in the U.S. District Court for the District of Hawai’i, challenging the agency’s May 26, 2026 certification of TMC USA’s application for a DSHMRA exploration license covering nearly 122,000 km² in the Clarion-Clipperton Zone. The plaintiffs allege that NOAA violated DSHMRA and the APA by failing to make the materials relevant to the application available for public review during the comment period, and they ask the court to vacate the certification. This claim previews the type of litigation that future permits may face. The lawsuit signals that U.S. environmental groups have the organizational capacity, legal expertise, and statutory tools to bring federal litigation against the permitting agencies and potential deep-sea mining industry participants.

B. Legal Risks Under International Law

The international legal risks are equally significant and encompass supply chain, operational, financial, and reputational exposure.

(1) UNCLOS recognizes that minerals on the seabed beyond national jurisdiction are the common heritage of humankind and prohibits unilateral claims outside the ISA’s regime. The ISA, the European Union, China, and other countries have condemned unilateral U.S. mining as a violation of international law. The DSHMRA also itself acknowledges that the deep seabed is the common heritage of mankind. Specifically, 30 U.S.C. § 1401 states that the U.S. “supported (by affirmative vote)” the 1970 U.N. General Assembly resolution declaring this principle. Challengers could argue that although the U.S. is not a party to UNCLOS, it has recognized that the deep seabed is the common heritage of mankind and its unilateral action violates customary international law.

(2) Under Article 139 of UNCLOS, states parties to UNCLOS bear a “responsibility to ensure” that their nationals and any entities effectively controlled by their nationals do not engage in activities in the Area outside the Part XI framework. Accordingly, any one of the 172 states parties to UNCLOS risks a claim under UNCLOS if they participate in or allow their citizens to participate in U.S.-authorized mining in the Area. Such a claim could result in an award of damages. In addition, under Article 153 and Annex III Article 18, such states parties could be impacted by ISA administrative measures including suspension or termination of ISA exploration contracts held by entities they have sponsored. Under Article 137, they could face market exclusion as other states parties implement their own obligation not to recognize rights to minerals recovered outside the ISA system. More broadly, states parties in this situation could experience diplomatic fallout from the undermining of the multilateral ocean governance regime.

(3) The practical obstacles to unilateral deep-sea mining span the chain of operations from vessel construction to mineral processing and end-market sales.

Given the global nature of supply chains and the maritime industry, it would likely be difficult to complete a deep-sea mining operation using only U.S.-registered and U.S.-affiliated resources. This challenge spans the full chain of ships, docking, processing, foreign suppliers, insurers, classification societies, and other logistical necessities. It is almost certain that any mining operation would have some exposure to an UNCLOS-affiliated nation, and with it, potential legal liability.

(4) Deep-sea mining industry participants may also face insurance and financial risks. Four major maritime insurers have excluded deep-sea mining from their underwriting activities. Globally, eighty-two financial institutions, which represent 24 trillion euros in assets, have issued statements of concern or added exclusions or conditions on deep-sea mining. A UNEP report warns that companies investing in deep-sea mining may find other companies less willing to do business with them.

III. Changes at the International Level

At the international level, the landscape has evolved as well. The ISA has moved closer to finalizing its mining code, and it began a formal inquiry into contractor non-compliance. Japan and the U.S. signed a memorandum of cooperation on deep-sea mining. Additionally, the Agreement on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction (the BBNJ Agreement) entered into force.

A. The BBNJ Agreement Kicks In

The BBNJ Agreement entered into force on January 17, 2026. It creates a multilateral mechanism for establishing Marine Protected Areas in areas beyond national jurisdiction, where activities such as mining may be prohibited or restricted. In Article 28, it also requires environmental impact assessments before states authorize activities.

The interaction between the BBNJ Agreement and the ISA regime remains uncertain because both bodies have authority over activities in the Area, with the ISA’s mandate covering minerals and the BBNJ’s mandate covering living organisms. The BBNJ could alter the legal context in which deep-sea mining operates, particularly regarding environmental standards and area-based conservation measures. ISA Secretary-General Leticia Carvalho has reaffirmed the ISA’s commitment to “working constructively” with the BBNJ institutions, and the issue was a topic of discussion at the March 2026 session.

B. Mining Code Unfinished

The ISA’s long-awaited mining code remains incomplete. In March and July 2026, Parts I and II of the ISA’s 31st Session concluded without agreement on the code. Member States discussed 29 out of 32 outstanding issues, and agreed to several in principle. But significant issues remain unresolved, like whether all forms of deep-sea mining will be subject to the regulations or just polymetallic nodule extraction.

ISA Secretary-General Carvalho had stated that the goal was to complete the code by the end of 2026. She argued that a finished code would reduce the appeal of U.S. mining and make attempts to mine outside ISA regulations “highly problematic.” The increased urgency prompted by American actions could push the ISA to complete the code more quickly, but the ISA previously failed to finalize the mining code to meet a 2023 deadline triggered when Naoero invoked the two-year rule in 2021. A third 2026 session had been proposed, but is reportedly no longer under consideration. The ISA is set to reconvene in March 2027 to continue work on the mining code.

C. The ISA’s Inquiry into Contractor Non-Compliance

One of the most significant developments at the ISA has been a formal inquiry into contractor non-compliance. In July 2025, the ISA Council adopted Decision ISBA/30/C/19, directing the Secretary-General and the Legal and Technical Commission (LTC) to investigate contractors at risk of breaching their contractual obligations. The inquiry focuses on the standard clauses for exploration contracts that require contractors to comply with UNCLOS, accept the ISA’s control over activities in the Area, act in good faith, and ensure that employees, subcontractors, and agents observe applicable law.

In January 2026, the Secretary-General circulated a request to all 21 contractors for information. All 21 responded, asserting they were in full compliance. Two contractors challenged the legality of the inquiry itself and reserved all dispute resolution rights. The LTC, in its preliminary report issued in March 2026, rejected these challenges and affirmed that the inquiry was consistent with the Convention. The LTC identified one contractor requiring specific attention for possible non-compliance and requested additional information, with a full report expected during the July session.

Greenpeace International submitted evidence to the ISA Secretary-General in March 2026, alleging that NORI and TOML have breached multiple provisions of their exploration contracts by facilitating TMC USA’s unilateral mining applications. If the LTC confirms a breach, the ISA could suspend or terminate the affected exploration contracts. Such a decision would carry enormous implications for TMC’s dual-track strategy.

The Council’s March 2026 decision further directed that all sponsoring states be reminded of their due diligence obligations and asked them to clarify any agreements that could undermine the common heritage principle.

In June 2026, NORI and TOML began proceedings before the International Tribunal for the Law of the Sea (ITLOS) Seabed Disputes Chamber (the Chamber), alleging that the inquiry process unfairly deprived them of an adequate opportunity to respond. In July 2026, the Chamber found that the ISA could continue the inquiry into contractor noncompliance, but needed to respect contractors’ due process rights and allow them to respond meaningfully to the questions posed within a reasonable time period. Also in July, the ISA Council voted to extend NORI’s exploration contract. On August 31, 2026, NORI and TOML jointly, and the ISA separately, filed reports detailing their compliance with the provisional measures awarded in July. NORI and TOML also asked the Chamber to consider ordering another round of compliance reports after the ISA’s February–March 2027 session.

The July 2026 orders demonstrate that the Part XI dispute resolution architecture is operational and can deliver enforceable relief. For the first time in a contentious decision, private contractors have successfully invoked compulsory international adjudication and obtained provisional measures requiring the ISA to observe due process in its compliance inquiries.

A decision from the Chamber is only one pathway within UNCLOS’s multi-track dispute resolution framework. Article 188(2) expressly provides that disputes concerning the interpretation or application of an exploration or exploitation contract may be submitted to binding commercial arbitration at the request of any party. Commercial arbitration has a viable and growing role to play in addressing disputes between contractors and their sponsoring states under the emerging generation of sponsorship agreements. As the deep-sea mining sector continues to evolve, the demand for experienced arbitration practitioners who can navigate overlapping legal regimes may increase.

Further, the orders are notable for what the Chamber placed on record: the ISA’s own public assurances, made before the tribunal, that it “will continue to honour” contractors’ due process rights and that “[t]here is no doubt regarding [its] commitment in this regard.” It also incorporated the ISA Council’s mandate “to ensure due process, transparency and fairness at every stage” of a compliance inquiry.

The Chamber used these assurances as the foundation for its provisional measures, holding the ISA to its word by ordering it to clarify its procedures, provide the factual and legal basis for its inquiries, and afford contractors a meaningful opportunity to respond within a reasonable timeframe. The ISA, like other regulatory bodies in the extractive sector, is now publicly committed to procedural standards, judicially supervised when it departs from them, and accountable to the entities it regulates.

D. The Japan-U.S. Memorandum of Cooperation

In March 2026, Japan and the United States signed a memorandum of cooperation on deep-sea mining, agreeing to share research and insights from their respective mining efforts through a joint working group. Japan has been moving ahead with its own plans to mine its continental shelf, motivated by a desire to reduce reliance on China’s dominance in rare earth metals.

The memorandum is not legally binding, instead marking support for U.S. deep-sea mining efforts. It did not specify whether Japan would assist the United States in national waters or international waters. As an UNCLOS signatory, Japanese cooperation in international waters could put the country at risk of breaching treaty obligations.

IV. Looking Ahead

The coming months will likely see a continuation of the new status quo in deep-sea mining ocean governance. The ISA will continue to work against the clock to finalize its mining code while seeking to keep the ambitious deep-sea mining industry participants at its gates from departing from the obligations set out by the international framework. Meanwhile, NOAA will continue processing TMC’s and other companies’ applications, and BOEM is set to continue advancing leases for domestic mining sites under federal control despite widespread opposition from territorial leaders, Indigenous communities, and environmental advocates.

The outcomes of these events will determine whether the American unilateral pathway represents a viable alternative to the multilateral framework or a legal and operational dead end.