Amos O Enabulele*
March 27, 2026, marked the anniversary of the announcement by The Metals Company (TMC) to apply for permits under existing U.S. mining legislation for deep-sea minerals in the high seas. In the announcement made on 27 March, 2025, TMC stated that it will apply for the permit in the second quarter of 2025. This was followed by President Donald Trump’s Executive Order of 24 April 2025, titled “Unleashing America’s Offshore Critical Minerals and Resources,” signalling the possibility of favourable consideration of TMC’s application when made.
The TMC, through its subsidiaries, Nauru Ocean Resources Inc. (NORI) and Tonga Offshore Mining Limited (TOML), holds exploration and commercial rights to two polymetallic nodule contract areas in the Clarion Clipperton Zone of the Pacific Ocean regulated by the International Seabed Authority (ISA), and sponsored by the governments of the Republic of Nauru and the Kingdom of Tonga, respectively.
Expectedly, the Secretary-General of the ISA issued a statement in response, decrying the United States’ potential unilateral approach. She stressed, inter alia, that “the United Nations Convention on the Law of the Sea … serves as the legitimate multilateral framework for governing our oceans and reflects general principles of international law and customary international law [and] proclaims the Area and its resources as the common heritage of humankind.” The statement further emphasised that “[a] direct corollary of this legal status is that no State may claim, acquire, or exercise sovereignty or sovereign rights over any part of the Area or its mineral resources. This includes a prohibition on appropriation and alienation by any State, or by any natural or juridical person.”
The Secretary-General’s statement received overwhelming support from ISA members. For instance, the Republic of Ireland, as did others, affirmed that “[u]nder international law, as reflected in the Convention, the Authority has the exclusive mandate to regulate the exploration and exploitation of mineral resources in the Area, which are the common heritage of humankind.” Ireland further emphasised that states, including sponsoring states, contractors, and natural and juridical persons, have obligations under the Convention and any applicable contracts with the Authority, particularly regarding involvement in activities outside the multilateral framework established by the Convention and the 1994 Agreement.
On its part, during the 30th session of the ISA Assembly in July 2025, the United States, an observer State to the ISA, issued a statement clarifying its position. The U.S. emphasised that it has consistently viewed UNCLOS provisions relating to traditional uses of the ocean, such as freedom of navigation and overflight, as reflecting customary international law (CIL) binding on all States. However, it maintained that it does not consider Part XI of the Convention or the 1994 Implementing Agreement to reflect CIL. On this basis, the U.S. asserted that it is not bound by the Convention’s rules governing seabed mining through the ISA.
That said, both sides of the legal argument have strengths and weaknesses and are likely to remain contested. There is presently no court or tribunal with clear contentious jurisdiction over the matter. The United States is not a party to UNCLOS and is therefore not bound by its dispute settlement mechanisms; it has also withdrawn from the compulsory jurisdiction of the International Court of Justice (ICJ). It is highly unlikely that the U.S. would consent to jurisdiction through a special agreement. Consequently, the issue is likely to remain within the realm of competing legal claims unless a valid jurisdictional basis, such as a jurisdictional clause treaty in force, emerges.
In our view, the critical issue is not whether the principle of the common heritage of humankind is CIL (we believe it is), but whether the institutional structure of Part XI has attained the status of CIL. On this score, some argue that the United States is bound due to its signature of the 1994 Implementing Agreement, despite not ratifying it. Others point to its participation in ISA meetings as an observer State as evidence of acceptance. However, such factors are, at best, indicative and far from conclusive.
Despite the ISA’s strong stance, neither the United States nor entities seeking permits under U.S. law appear deterred. Less than a year after TMC’s announcement, on 23 March 2026, Canada’s Deep Sea Minerals Corp. announced that it had submitted an application to the U.S. National Oceanic and Atmospheric Administration (NOAA) pursuant to the Deep Seabed Hard Mineral Resources Act (DSHMRA). The application seeks an exploration licence for polymetallic nodules in a defined area of the Clarion-Clipperton Zone in the Pacific Ocean and was submitted through the company’s U.S. subsidiary, American Ocean Minerals Corp.
What is particularly alarming is that Deep Sea Minerals Corp. is registered in Canada, a member State of the ISA that actively participates in its activities. To that extent, and in light of UNCLOS (articles 136-138), the application directly engages Canada’s international obligations and may potentially indicate a violation of UNCLOS (articles 136-138). This is not a question of attributing the company’s conduct to Canada, but rather of Canada’s direct obligation not to undermine the Convention’s framework. Alternatively, viewed through the lens of the Barcelona Traction Light and Power Co. Ltd, (Belgium v Spain), Preliminary Objections, ICJ Rep 1964, 6 the fact that Canada alone would be entitled to exercise diplomatic protection over Deep Sea Minerals Corp under CIL lends another layer to the weight of Canada’s obligation.
While TMC’s anticipated application raises concerns, the present development is arguably more troubling. Unlike TMC, which is an American company and operates within the contested position of the United States vis-à-vis UNCLOS, Canada is unquestionably bound by the Convention. This distinction significantly heightens the legal and political implications of the current situation.
The more pressing concern is what these developments mean for developing and small island States. Initially, the issue involved only the United States and a U.S.-registered company. However, within less than a year, the practice appears to be expanding to include entities linked to States that are active ISA members. This development reinforces longstanding fears that unilateral exploitation of seabed resources will benefit only a select group of technologically advanced States, to the exclusion of others. Whether directly, as in the case of the United States, or indirectly through corporate structures of ISA member States, African States and other developing States lack the capacity to participate meaningfully outside the ISA framework.
This trend fundamentally challenges the principle of the common heritage of humankind and signals the emergence of a competitive race for deep-sea resources dominated by developed nations. Developing States risk becoming mere spectators, effectively stripped of their shared ownership in these resources. Humanity thus stands on the brink of returning to the very conditions that necessitated the establishment of the common heritage principle.
In 1967, Malta’s Ambassador to the United Nations, Arvid Pardo, proposed reserving the deep seabed for peaceful purposes and for the benefit of all mankind. His intervention laid the foundation for the multilateral framework later embodied in UNCLOS. In his famous speech to the First Committee of the UN General Assembly on 1 November 1967, Pardo warned of the dangers of technological advancement leading to the unilateral appropriation of seabed resources. He cautioned that such developments could have “incalculable” consequences for humanity.
These concerns ultimately shaped the provisions of Part XI of UNCLOS, which enshrine the principle that the Area and its resources are the common heritage of humankind. Articles 136 and 137 prohibit States and private entities from claiming or exercising sovereignty over any part of the Area or its resources. Instead, all resources are vested in mankind as a whole, with the ISA acting on its behalf. Accordingly, mineral resources may only be explored and exploited under the ISA’s authority and in accordance with its rules and procedures.
Under Article 133, the “resources” of the Area include all solid, liquid, or gaseous mineral resources in situ, such as polymetallic nodules. The ISA has issued numerous exploration licences, covering polymetallic nodules, sulphides, and cobalt-rich crusts, with 30 contracts awarded as of December 2024.
It is widely acknowledged that Part XI has long been the most contentious aspect of UNCLOS. It delayed the Convention’s entry into force and remains the primary reason the United States has not ratified it. Today, it continues to generate significant legal and political tensions.
As a non-state party to the UNCLOS, the United States relies on the Deep Seabed Hard Mineral Resources Act of 1980, which established a domestic licensing regime for seabed mining. Similar legislation was adopted by several other States during the negotiation of UNCLOS. However, unlike the United States, those States later ratified the Convention and aligned their practices with the multilateral system.
Finally, it must be acknowledged that frustration with the ISA’s slow progress has contributed to the current situation. Ongoing divisions among member States, particularly regarding proposals for a moratorium, precautionary pause or even some ideas around outright ban of seabed mining, have created uncertainty about the future of seabed mining under the auspices of the ISA. In this regard, we must recall that a reason advanced by TMC for turning to the U.S was that the U.S’s “DSHMRA, along with its implementing regulations completed by NOAA in 1989 … provide a robust, predictable regulatory regime while the International Seabed Authority (ISA) has not yet adopted the Exploitation Regulations in breach of its treaty obligations under UNCLOS and the 1994 Agreement”.
While environmental concerns are legitimate and must be addressed, we fear that the greater environmental risk arguably lies in unilateral approaches rather than within the multilateral framework of the ISA. It is therefore important that environmental concerns are not used as a tool to unnecessarily stall or frustrate the ongoing negotiations on the exploitation regulations, as this may be counterproductive in the long run. This is because, although a State’s unilateral regulatory regime, as the United States’ may purport to provide robust environmental protection, however, if implemented, its standards are likely to fall below those required by the ISA. Moreover, there would be no external mechanism to independently assess the adequacy or effectiveness of such protections.
The bottom line remains that the apparent obstacles to concluding the exploitation regulations risk undermining both the relevance of the ISA and the ability of developing states to benefit from seabed resources.
*Professor of Public International Law
Executive Director, Centre for Community Law