On 30 September 2021, the Supreme Court released its much-anticipated judgment unanimously dismissing the appeal by Trans-Tasman Resources (TTR) in the long-standing legal dispute surrounding its application for seabed mining consents under the Exclusive Economic (Environmental Effects) Act 2012 (EEZ Act). The proceedings have attracted considerable international and domestic interest from legal scholars and commentators, in addition to the concerns of environmental non-government organisations, affected iwi, and commercial fishing parties who opposed TTR’s application (opposing parties). The judgment has far-reaching implications for marine management in terms of state implementation of international law obligations and Indigenous rights, including the importance of tikanga Māori (Māori law and custom) in Aotearoa New Zealand. It provides valuable guidance and directions to decision-makers as to the scope and function of the EEZ Act, in line with New Zealand’s international obligations, and Crown obligations under Te Tiriti o Waitangi/the Treaty of Waitangi (the Treaty).