After years of litigation, the Higher Regional Court of Hamm rendered its final decision in the most prominent German climate litigation case after Neubauer et al. v. Germany: Lliuya v. RWE AG. Saúl Lliuya, a Peruvian farmer and mountain guide, sued RWE for the payment of appropriate measures aimed at protecting his property against a potential glacier flood. Although the Court rejected the claim in the end, the judgment has been celebrated as a “Success without Victory” due to the potential precedent effect in terms of corporate liability (see here, here and here).

The true significance of the Lliuya v. RWE decision lies not in its dismissal of the plaintiff’s claim, but in the court’s reasoning on extraterritoriality, causality, and preventive protection. These legal findings provide a comparative reference point that may inform and strengthen transnational climate litigation, particularly before human rights monitoring bodies, thereby contributing to the pursuit of climate justice across the South–North divide. The decision also has a synergic effect vis-à-vis the recognition of a reinforced due diligence of the States regarding climate change and their emerging obligations under international law, as explained in the ICJ Advisory Opinion of 23 July 2025 and in the Inter-American Court’s Advisory Opinion No. 32/25.

Transnational litigation in national jurisdiction

In essence, the complaint had asked the Court to declare that RWE should bear the costs of appropriate protective measures in favor of Lliuya’s property against a potential glacier flood from the “Laguna Palcacocha” in proportion to its share of 0.38% of global greenhouse gas (GHG) emissions (pp. 15 f.). While the Court found that the complaint is admissible and in principle conclusive on the merits (p. 24), in the end, it considered it unfounded as “a concrete threat of damage to the plaintiff’s property […] is not to be expected with the probability required under Section 1004 (1) sentence 2 BGB” (p. 95). It therefore dismissed the action based on an expert report indicating that the probability for a Glacier Lake Outburst Flood (GLOF) to affect Saúl’s property in the upcoming 30 years was only 1% (pp. 24, 101) (on the controversies surrounding this report see here, here and here).

Lliuya v. RWE exemplifies how litigation can challenge the legal architecture that shields historical emitters by treating climate change as purely political, while Global South communities disproportionately suffer impacts they themselves have not caused.

The decision confronts structural inequalities in the distribution of harm and responsibility, recognizing that private actors, particularly major emitters, may bear civil liability for their proportional contribution. It conceptualizes environmental harm as cumulative, transboundary and attributable, thereby opening jurisprudential space for future cases.

The fact that this recognition was made through the interpretation of traditional civil law instruments signals that the existing legal framework, if interpreted progressively and in dialogue with climate science, can serve justice in the Anthropocene. This provides a clear argument not only for future cases in Germany, but also in any other country with similar provisions – especially in civil-law countries that have developed their civil codes looking at Roman law.

This is the case for most of Latin-American countries, where norms about preventive protection of possession or property could be repurposed to address environmental risks stemming from transnational pollution. These tools allow for anticipatory intervention, even in the absence of immediate damage, and align with a vision of law that embraces precaution and intergenerational equity.

Furthermore, the case signals the value of incorporating attribution science into legal reasoning. By quantifying the historical emissions of individual companies and linking them to specific risks, plaintiffs may overcome the epistemic opacity that has traditionally benefited large polluters. The increasing availability of data, such as from the Carbon Majors Database, can underpin claims grounded in shared responsibility and proportional causation. For countries of the South, highly vulnerable to climate impacts, this development provides a precedent and a methodology: responsibility can be argued concretely with data and grounded in existing legal traditions.

Significance for transnational climate litigation before human rights monitoring bodies

The legal reasoning laid out in the decision can also influence regional and international human rights jurisprudence.

First, it must be noted that, as a general rule, human rights monitoring bodies only examine whether States have breached their obligations under the respective human rights regime. So far, corporations cannot be brought before human rights courts, commissions or committees directly. Nonetheless, States are required to regulate the behavior of third parties as part of their positive human rights obligations, which, inter alia, include the enactment of corresponding legislation and investigations into alleged corporate breaches.

In this sense, monitoring bodies, such as the Inter-American Court of Human Rights (IACtHR), have explicitly recognized first tendencies towards the regulation of extraterritorial corporate conduct by the home State to prevent negative impacts on the human rights of individuals residing outside the State where the corporation is registered (AO No. 23, para. 151). In its recent Advisory Opinion No. 32 on “Climate Emergency and Human Rights”, the IACtHR further emphasized that companies, too, have obligations and responsibilities with respect to climate change and its negative impacts on human rights, establishing detailed obligations of States to regulate and monitor companies’ conduct in relation to climate change (paras. 346 f.).

In particular, the reasoning of the Higher Regional Court of Hamm may inspire human rights bodies in interpreting norms and obligations related to climate change. Though based on national law, its arguments could inform human rights jurisprudence, particularly on extraterritoriality, causality, and preventive protection as argued in the following.

Extraterritoriality

The national judges affirmed that the location of the plaintiff did not prevent him from asserting a claim against RWE, as the norm neither required a current legal relationship of the defendant to the impairment or the source of disturbance, nor proximity between the source of disturbance and the affected property (p. 39). This reflects the “global neighborhood” created by GHGs and their effects that travel across national borders and do not materialize where they have been emitted. Considering the extraterritorial effects of climate change and the general possibility that carbon majors can be held responsible for extraterritorial harm caused by their substantial emissions could motivate human rights monitoring bodies to extend or further strengthen the extraterritorial application of human rights regimes in the context of climate change, which would particularly facilitate South-North litigation by claimants disproportionately affected by climate change that seek to target high emitting States.

This holds particularly true regarding the European Court of Human Rights (ECtHR), whose restrictive approach to extraterritoriality under the European Convention led to the dismissal of Duarte Agostinho and Others v. Portugal and 32 Others. The Court found no evidence that the respondent States exercised “effective control of an area outside its national territory bringing the applicants within its jurisdiction ratione loci”, nor that they exercised authority or control over the applicants under Article 1 case-law (paras. 181 f.).

By contrast, the IACtHR in Advisory Opinion No. 23 on “Environment and Human Rights” held that victims of transboundary environmental harm fall under a State’s jurisdiction if a causal link exists between acts or omissions within its territory and human rights violations abroad (paras. 101, 103), adding that States must exercise effective control over activities causing such harm (para. 104) – a standard further developed by the Committee on the Rights of the Child in Sacchi et al. v. Argentina et al., which considered that

“children are under the jurisdiction of the State on whose territory the emissions originated […] if there is a causal link […] when the State of origin exercises effective control over the sources of the emissions” (para. 10.7).

The IACtHR’s standards on extraterritorial jurisdiction close important accountability gaps in climate-related human rights law, particularly relevant for South–North litigation against (historically) high emitters of the Global North by affected communities in the South. However, such claims cannot be pursued within the Inter-American System due to its limited jurisdiction. In this context, the Higher Regional Court of Hamm’s acceptance of Lliuya’s extraterritorial claim sends a positive signal as it supports and strengthens progressive standards, which originated from courts in the Global South. From a Council of Europe member State, a decision, which has attracted worldwide attention and is widely received and welcomed in legal practice and civil society, could provide impetus for the ECtHR to reconsider its restrictive approach in future years.

Causality

The Higher Regional Court of Hamm clarified that for Section 1004 (1) BGB, the relevant link is legal, not physical causality, finding RWE’s emissions since 1965 causal for the endangerment of Saúl’s property (pp. 42, 46 f.). The judgment stated that “it was already foreseeable in the mid-1960s for an optimal observer in the role of an energy producer that anthropogenic greenhouse gas emissions would lead to global warming and the associated consequences” and concluded that RWE’s 0.38% share of global industrial emissions could be considered significant (pp. 49, 51 ff.). It stressed that significance cannot be assessed by size alone, but comparatively, determining “which causal contribution has significantly increased the risk” (p. 51).

This reasoning can equally inform and strengthen human rights jurisprudence, which both at the stage of admissibility and merits needs to deal with causal links between GHG-emitting activities under the jurisdiction of States and the (potential) harm inflicted upon fundamental interests protected by human rights. Where human rights bodies opt for a certain level of causal contribution (e.g., “substantial” or “significant”), the comparative model could prove useful to characterize, especially, the GHG emissions attributable to States from the Global North as significant, providing a further rejection of the “drop in the ocean” argument. Similarly, the argument that a single polluter from a group of multiple polluters with causal contributions to a harm or risk of harm may be held responsible (p. 64) can equally be used to support the argument that also a single State from a large group of polluting States can be held responsible for its emissions.

Yet, the question remains whether human rights monitoring bodies will adopt a similar approach, limiting responsibility to a State’s fair share of (potential) damage, or whether it will be too burdensome to require plaintiffs to sue all high-emitting States, allowing instead for full responsibility with recourse against others. Such questions may become increasingly relevant as applicants seek costs for adaptation measures or redress for losses and damages against multiple respondent States before human rights bodies in the future. In this sense, the first wave of climate litigation before human rights monitoring bodies that have served to set the scene through fundamental findings on the interpretation of human rights norms in the context of the current climate crisis, the next generations of climate cases could lead to further specifications of those standards that could build on and benefit from the findings provided in Lliuya v. RWE. While the Court’s statements on causality may rather take a back seat where human rights monitoring bodies prefer to refer to the fundamental standards established by the International Court of Justice (ICJ) in its Advisory Opinion on “Obligations of States in Respect of Climate Change”, the Lliuya decision could still provide them with additional input to further strengthen and potentially refine their arguments regarding issues of cumulative causality and corresponding questions of shared responsibility within the context of South-North litigation. Even though Lliuya operates in the setting of corporate liability, the approach taken by the Higher Regional Court regarding causation, attribution and responsibility of multiple polluters overall matches the rather general standards developed by the ICJ, who observed

“that while climate change is caused by cumulative GHG emissions, it is scientifically possible to determine each State’s total contribution to global emissions, taking into account both historical and current emissions” (para. 429), while “[f]actual questions arising in the context of attribution and apportionment of responsibility are to be resolved on a case-by-case basis” (paras. 429, 432; see also here for issues of causality and attribution that remain underdeveloped in the ICJ decision).

In this sense, Lliuya v. RWE provides international and national courts with a concrete example of how such distribution of responsibility based on cumulative causation could look like in the specific case – whether addressing the responsibility of a single State or corporation.

Preventive protection

Lastly, the application of Section 1004 BGB shows how, in cases of anthropogenic climate harm, polluters can not only be required to repair harm that has already materialized, but also to take measures necessary to “prevent the impairment from occurring”, reversing the success of the disruptive activity or at least rendering it ineffective (pp. 35 f.). In this sense, the plaintiff has the possibility to sue for injunctive relief (pp. 35 f.). As human rights monitoring bodies in principle require for a petition to be admissible that the harm has already occurred, the possibility to sue a polluter for future harm under national law could motivate human rights monitoring bodies to consider the admissibility of climate change-related claims concerning future harm, particularly in light of the significant and forensically problematic delay between GHG emitting activities and the materialization of the harm. Such an approach could find support in the ICJ’s findings on State obligations of prevention in its Climate Advisory Opinion, where the Court recognized that “the standard of due diligence for preventing significant harm to the climate system is stringent” and that “a heightened degree of vigilance and prevention is required” in the context of climate change (para. 138). The ICJ further underscored that the precautionary principle guides the required standard of conduct in the fulfillment of a State’s duty to prevent significant harm (para. 294).

In this spirit, the IACtHR has already transferred the principle of prevention, originally rooted in international environmental law, to human rights obligations in the context of (transboundary) environmental harm in AO No. 23 and regarding the global climate crisis in its recent AO No. 32 (see particularly AO No. 23, paras. 127 ff.; AO No. 32 paras. 228 ff., 275 f., 296, 352 f., 501-504, 553). Those obligations include the duty to mitigate climate harm and should enable claimants to claim a violation of this obligation when adequate mitigation targets are not met, even if harm to the detriment of the claimants has not yet occurred.

Conclusion

Lliuya v. RWE is more than a legal dispute; it challenges the impunity of the carbon economy and urges jurists, especially in the Global North, to look beyond borders to protect those most affected by climate breakdown. Even without binding international frameworks, it shows that legal responsibility can be argued and demanded, reclaiming law as a tool of climate justice across borders. The decision affirms that major emitters can be held accountable for their proportional contribution to global harms and that national courts can play a vital role in articulating climate responsibilities. As such, Lliuya’s true significance lies in inspiring future action within national and international courtrooms, thereby challenging governance asymmetries, and reaffirming that justice is possible even in fragmented legal landscapes.