Hamm Higher Regional Court dismisses Lliuya v RWE climate action – Liability on the merits confirmed
"Successful failure" – Higher Regional Court denies payment claim but emphasises that large CO₂ emitters can be liable under civil law for damage due to their responsibility for climate change.
Background
Peruvian mountain guide Saúl Luciano Lliuya has been demanding since 2015 that RWE, as Europe's largest CO2 emitter, should take a proportionate interest in local flood protection measures for his house and village. The accusation: As a result of accelerated anthropogenic climate change, glaciers are melting inexorably, while the level of the glacial lake above his village continues to rise, which could trigger a dangerous outburst flood ("GLOF") that could potentially reach his house. To prevent this, the water level of the lake could be permanently lowered through targeted lowering measures – estimated to cost around EUR 3.5 million – and RWE would be expected to contribute a proportionate amount of this cost, according to Lliuya. "Proportionate" here means in line with RWE's contribution to the cause. This claim is based on a scientifically determined contributory factor of the company, which, according to the Carbon Majors Report, was initially responsible for 0.47 % and is now responsible for "only" 0.38 % of all CO2 emissions since industrialisation began.
Course of proceedings
After the action was brought before Essen Regional Court (2015) and disallowed at first instance (2016), Hamm Higher Regional Court issued an extensive order for evidence in 2017. This was followed by two site visits to Huaraz (Peru), two expert opinions on hydrology and climate modelling as well as various challenges on grounds of conflict of interest – with court and expert costs amounting to around EUR 800,000.
The expert opinions were intended to clarify the court's first question, namely whether there was a risk of serious damage to the specific property of the plaintiff in the next thirty years due to flooding or a mudslide. On the very first day of the hearing in March 2025 it became clear that the experts considered the risk to be very low.
As RWE's share of global greenhouse gas emissions appears to have fallen from 0.47 to 0.38 %, the claimant's lawyer, Dr Roda Verheyen, also declared that part of the claim – 0.09 percentage points to be precise – was settled.
On 28 May 2025, the 5th Civil Panel handed down its final judgment (5 U 15/17) after almost ten years of proceedings. The second appeal on a point of law was not admissible; however, the claimant is free to file a complaint against the denial of leave to appeal with the Federal Court of Justice.
Overview of the decision
Liability is possible in principle
Lliuya based his claim not just on the performance of work or services without instruction, but also on a claim for removal and injunction under section 1004 (1) sentence 2 German Civil Code (BGB), according to which a property owner may demand that a disturber cease and desist from "imminent interference″ with their property. The disturber must then bear the necessary costs of removal regardless of fault. Hamm Higher Regional Court considers such liability of German companies for the consequences of climate change in other countries to be possible in principle. Even the great distance between the German energy producer's power plants and the claimant's place of residence was no obstacle. On this point, the Higher Regional Court disagreed with the first instance, which had dismissed Lliuya's claim on the grounds that a single company could not be held accountable for global climate change.
The court confirmed that scientific as well as adequate causality must always be demonstrable and that even a small proportion of emissions can be sufficient to be considered as interference. Approvals under public law and compliance with environmental limits only have an "indicative" effect (section 906 German Civil Code (BGB)) and do not automatically result in an exclusion of liability (autonomy of private law).
Hurdle of causality and risk
The claim fails solely because the danger is not sufficiently concrete: The expert witness estimated the probability of a flood occurring in the next 30 years at ≈ 1 %; even if it did occur, the water would only come up to about 20 cm high around the house. This means that there is not "sufficient probability" of an imminent encroachment – a mandatory element of sections 1004, 906 German Civil Code (BGB).
The panel deliberately limited the examination to the last link in the causal chain – the immediate risk prognosis – and left all upstream legal questions open. It is thus signalling to future claimants that detailed fact-finding on risks and probability of occurrence will be essential.
Legal classification
The decision fits into the European discussion on Article 17 Rome II Regulation: Courts will only take into account legal approval requirements as "rules of safety and conduct" insofar as they are appropriate. This means that approval compliance remains an important, but not conclusive, line of defence. Hamm Higher Regional Court is also raising the bar for successful climate litigation by placing the forecast of specific dangers and damage at the heart of the burden of demonstration. Nevertheless, the way is basically paved for future claims for damages or adjustment actions – in what NGOs are calling a "success despite defeat".
Practical implications for companies and recommendations for action
- Approval compliance remains essential but is not a "liability shield". Approval audit: Check older permit certificates for example in Germany under the German Emission Control Act (BImSchG) for references to climate change mitigation.
- Increasing evidentiary risk: Future claimants may request extensive expert opinions and data sets ("discovery light" in German civil proceedings). Identify and document potential damage points of your emissions so you can refute allegations at an early stage ("climate-risk mapping"). Archive operational, emissions and weather data in a structured way so you are prepared for court requests for expert witnesses.
- Individual instances of damage due to climate change (flooding, forest fires, heat) are easier to quantify than "global average damage" – the number of cases is likely to increase.
- ESG reporting and litigation narratives must be consistent: Contradictions between sustainability communication and procedural standpoints provide a target for attack.
- Contractual rules of recourse: Check whether climate risks can be distributed along the supply chain through clear cost-sharing and exemption clauses.
Outlook: Is there a real risk of an outburst flood (or other climate-related natural disasters) leading to a wave of legal action?
The claimant has already announced that he will lodge a complaint against denial of leave to appeal with the German Federal Court of Justice. However, due to the very low risk of an outburst flood as a result of glacier melting, a wave of legal action against the energy giant, at least from residents of the city of Huaraz, is not to be expected. This was stated by presiding judge Dr Meyer at the pronouncement of the judgment: "The case does not invite imitation and will probably remain the only one of its kind, at least in my lifetime″. Elsewhere, however, a court spokesperson explained that the claim put forward by the claimants was theoretically possible, meaning that the court could have decided differently if the evidence had been different.
Further claims could therefore follow, and Verheyen, the representative of the claimant, already has other clients, e.g. in Nepal.
To acquire the necessary evidence claimants may start to widen their nets and bring cases against multiple defendants. In some jurisdictions this is already happening. In New Zealand, Smith v Fonterra [2024] NZSC 5, a unique nuisance claim is being brought against seven of New Zealand’s biggest companies. In the United States the US Justice Department has recently filed complaints for declaratory and injunctive relief to prevent the states of Hawaii, Michigan, New York and Vermont from bringing legal claims against oil and gas companies.
Quantifying damages in climate litigation cases in monetary terms will always be challenging. Both the Hamm case and Dutch Court of Appeal’s decision in Shell v Milliedefensie last year imply that some form of remedy, possibly in line with the International Energy Agency’s Net Zero pathway published in May 2021, will be awarded in the future. Judges will likely be wary about being drawn into complex policy decisions as to how future climate targets are set for individual companies. A negative injunction containing an absolute prohibition on certain activities may provide a simpler and more certain way to grant relief, especially if the claimants are bringing the claim for strategic reasons as opposed to recovering a monetary award by way of damages. If a political solution to the climate crisis does not emerge this will likely become an increasingly attractive option for claimants that have resorted to litigation out of desperation and frustration with the status quo. For companies, this means that early data collection and integrated climate risk management are the most effective shield against waves of costly climate litigation.
