The Grantham Research Institute on Climate Change has issued a report tracking key trends and developments in global climate change litigation. The report finds that courts increasingly view countries’ obligations to act on climate change as a matter of legal duty and not political expediency.

Titled, ‘Global Trends in Climate Change Litigation: 2026 Snapshot,’ the report tracks data from 2025 and highlights new developments through to May 2026, drawing chiefly from the Climate Litigation Database maintained by the Sabin Center for Climate Change Law at Columbia Law School.

Its analysis focuses on five themes:

• The maturation of climate change litigation as a dimension of global climate governance;
• The field’s expansion and innovation across new locations, actors, and legal theories;
• The current pushback against climate action in general – and climate litigation specifically;
• The increasing complexity, as evidenced by the politics and trade-offs involved in the implementation of climate policies; and
• The state of knowledge about the implementation and impacts of climate litigation.

The report reveals that between January 2025 and December 2025, 249 new climate cases were filed, with the total since 1986 surpassing 3,600 cases. More than a quarter of these have been filed since the Paris Agreement on climate change was adopted in 2015. Cases have been filed in 62 countries, with the US seeing the highest number of cases. In 2025 alone, 151 new cases were filed in the US, out of a total of 2,078.

On maturity, the report finds that a growing number of court decisions find climate action to be a matter of legal duty. These include the recent advisory opinions from the International Tribunal on the Law of the Sea (ITLOS), the Inter-American Court of Human Rights (IACtHR), and the International Court of Justice (ICJ). Increasingly, courts entertain “polluter pays” and corporate framework cases, but none have resulted in an injunction prompting behavior change or an order of the payment of damages. The most common type of cases involving corporate actors are “climate-washing cases,” challenging narratives about the low-carbon transition.

On expansion and innovation, the report points to a widening circle of climate litigants and new types of claimants. It anticipates the next wave of climate litigation cases to focus on carbon dioxide removal and storage infrastructure, emissions from powering large data centers, and the link between climate change and other environmental challenges, such as plastic pollution.

The report finds that opposition to climate litigation is increasing in terms of the scale, coordination, and institutional depth, particularly in the US. At the same time, this pushback has given rise to “a substantial and growing countervailing wave of protective climate litigation,” according to the report.

The report underscores that “[n]on-climate-aligned cases reflect the complex trade-offs of the implementation phase of the energy transition.” This is evidenced by an uptick in just transition litigation and “green versus green” cases, challenging climate action from the point of view of justice and fairness and questioning climate policies in terms of their impacts on other parts of the environment. In addition, recent cases have questioned the manner of the implementation of climate adaptation measures,suggesting potential adaptation-mitigation trade-offs. 

In terms of impacts and implementation of climate litigation, the report concludes that:

• Climate-aligned judgments do not automatically lead to policy change;
• Charting the anticipated impacts and unintended consequences of positive judicial decisions presents challenges; and
• Sustained political will and legal follow-through are necessary to implement climate judgments.

Now in its ninth edition, the report was launched on 25 June, during London Climate Action Week 2026. [Publication: Global Trends in Climate Change Litigation: 2026 Snapshot] [Summary Report] [Publication Landing Page] [SDG Knowledge Hub Story on 2025 UNEP Report on Climate Change Litigation]