Centro de Ex Combatientes Islas Malvinas La Plata (CECIM) et al. v. Rockhopper Exploration PLC et al.

On September 1, 2026, the Asociación Civil de Abogados, Abogado/as y Profesionales Ambientalistas (AAdeAA), and the Centro de Ex Combatientes Islas Malvinas La Plata (CECIM) filed a preventive collective environmental damage action against Rockhopper Exploration PLC and Navitas Petroleum Development and Production Limited before the Federal Court of Río Grande. Plaintiffs seek to prevent the development of the “León Marino” (Sea Lion) offshore oil project, located approximately 220 kilometers north of the Malvinas Islands (Falkland Islands), on areas of the continental shelf over which Argentina claims sovereignty.

Plaintiffs allege that the large-scale offshore oil project is proceeding without an environmental impact assessment or authorization from the competent Argentine authorities and poses serious risks to marine and coastal ecosystems. They invoke, among other provisions, Argentina's General Environmental Law, Law No. 27,520 on Global Climate Change Adaptation and Mitigation, the UNFCCC, and the Paris Agreement. The complaint argues that the project would exacerbate climate change through greenhouse gas emissions and alleges that its development would generate approximately 9 million metric tons of CO2, with more than 100 million metric tons of CO2 resulting from combustion of the oil produced. Plaintiffs also invoke the human right to a healthy environment, a fundamental right to a healthy climate, and the rights of Nature.

On September 16, 2026, Judge Mariel E. Borruto granted a precautionary measure ordering Defendants to refrain from materially implementing the project, including drilling, installation of permanent subsea and production infrastructure, commencement of commercial hydrocarbon extraction, and related terrestrial and port works. The suspension remains in effect until the environmental impact assessment procedure required by Argentine law is conducted and the competent authority issues a decision, or until otherwise ordered by the court.

In granting interim relief, the court applied the preventive and precautionary principles and found that the plaintiffs were not required at this stage to establish with certainty that environmental damage would occur. The court also relied on Inter-American Court of Human Rights Advisory Opinions OC-23/17 and OC-32/25, emphasizing the autonomous and collective dimensions of the right to a healthy environment and the protection of ecosystems and present and future generations in the context of climate change.

As of September 2026, the underlying preventive action remains pending.