A Canadian deep-sea mining company may become the first to commercially mine the international seabed under a controversial U.S. executive order that bypasses United Nations regulations. A recent legal analysis suggests that this could place Canada in violation of international law.The U.S. National Oceanic and Atmospheric Administration (NOAA) recently announced that an application made by Vancouver-based The Metals Company (via their U.S. subsidiary, TMC USA) is fully compliant with NOAA regulations. The next steps include publication of a draft environmental impact statement for public comment, which TMC expects will lead to a permit to mine the seabed by the first quarter of 2027.As demand for critical minerals grows, governments worldwide are increasingly looking past their borders and coastlines towards the deep sea for mineral resources. Of particular interest are the billions of tonnes of polymetallic nodules rich in cobalt, nickel and rare earth elements that lie unattached on the seafloor, four to six kilometres below the water surface. Modern engineering techniques are making polymetallic nodule mining more economically viable for mining companies. However, a complicating factor is that most polymetallic nodules lie in international waters, outside any single country’s territory. Around 90 per cent of UN member states have ratified the United Nations Convention on the Law of the Sea (UNCLOS), which asserts that the deep sea is the “common heritage of mankind” and its resources are “vested in mankind as a whole.” The United States never ratified the treaty.U.S. moves to mine the international seabed Polymetallic nodules lying on the seabed. The nodules are rich in cobalt, nickel and rare earth elements. (NOAA) In April 2025, U.S. President Donald Trump signed an executive order that aims to fast-track mining permits for seabed minerals in areas beyond U.S. national jurisdiction.Put simply, the U.S. wants to start issuing permits to mine areas of the seabed that are not owned by the U.S. or any other country, outside of the UN’s International Seabed Authority (ISA) regulations. The same month, TMC USA applied for a first commercial recovery permit to mine approximately 25,000 square kilometres of seabed in the Pacific Ocean. This application was later amended to 65,000 square kilometres, an area more than twice the size of Vancouver Island. Negative reception of the U.S. executive orderIn response to Trump’s executive order, the ISA Secretary-General Leticia Carvalho asserted that “no state has the right to unilaterally exploit the mineral resources of the [deep sea] outside the legal framework established by UNCLOS.”UN member states have been working towards a regulatory framework for commercial mining of deep-sea minerals since 2014, under the guidance of the International Seabed Authority. However, as of June 2026, the regulations remain unfinished.Representatives from the U.S. argue that their country neither signed not ratified UNCLOS, and therefore, has no obligation to adhere to the ISA permitting process, stating “the United States is not bound by the Convention rules dealing with seabed mining through the International Seabed Authority.”They instead cite the U.S. Deep Seabed Hard Minerals Resources Act, a little-used legislative pathway through which some exploration permits were handed out in the early 1980s but has since laid dormant. Leticia Carvalho, Secretary-General of the International Seabed Authority, addressing the ISA Council. (IISD/ENB/Anastasia Rodopoulou), CC BY-NC-SA Potential legal ramifications for CanadaWhether or not the U.S. actions are legal remains to be seen. However, this issue raises a second question. Will Canada, a state party to UNCLOS, face any legal ramifications if the American subsidiary of a Canadian company begins mining international waters under U.S. permits?This question is the focus of recent legal analyses of UNCLOS articles 137-139 from independent lawyers and a recent report by Greenpeace.For UNCLOS member states, their obligations under the treaty are very clear: these states not allowed to mine independently, and they are also bound not to recognize nor participate with any unilateral mining.Crucially, member states also have a “responsibility to ensure” that no enterprise or person under their jurisdiction are involved with any of these unilateral mining activities.If Canada is found to have breached any of these rules, this would leave the country vulnerable to being brought to disciplinary hearings at the Seabed Disputes Chamber. As an UNCLOS state party, Canada would be legally obligated to comply with a disputes hearing and ruling, and to pay any damages ordered.The Metals Company is pursuing the U.S. regulatory pathway through their U.S.-based subsidiary company. However, TMC USA has only existed by that name since January 2025, meaning that critical data, funds and proprietary designs used for mining are likely carried over from the Canadian parent company TMC, or other TMC subsidiaries.If an American subsidiary has arguably no functional independence from their Canadian parent company, Canada could have an obligation and responsibility under UNCLOS to ensure the company is not participating in mining activities that potentially violate UN regulations. Canadian government’s position Canadian delegates at an International Seabed Authority meeting in March 2025. (IISD/ENB/Angeles Estrada Vigil), CC BY-NC-SA In 2023, the Canadian government announced its support for a moratorium on commercial seabed mining in international waters. However, since then the government has remained silent on the issue of deep-sea mining. In a recent public letter, environmental and social justice organizations and community groups called on the government to “publicly denounce efforts by a Canadian company to engage in unilateral deep-sea mining,” as well as to reaffirm its commitment to UNCLOS and to a moratorium on deep-seabed minerals.With the upcoming ISA assembly meeting scheduled in July 2026, all eyes will be on Canada to see if they recognize a responsibility to challenge TMC and the U.S. government’s actions, or continue to remain silent.Cara B. G. James receives funding from the Natural Sciences and Engineering Research Council of Canada.