Lliuya v RWE AG - Expanding climate impact litigation

The German court handed down its decision on 28 May 2025 dismissing the long-running climate impact litigation case of Lliuya v RWE¹, heard before the Higher Regional Court of Hamm, Germany, between 17 and 19 March 2025. Notwithstanding the result, this is an important case which has confirmed the principle that climate impact claims can be brought against fossil fuel and energy companies.  Fundamentally, the German court acknowledged that where claimants can demonstrate a real threat of harm caused by climate change, they can bring claims against tortfeasors or "polluters". 

The case first brought almost 10 years ago by Saúl Luciano Lliuya, a Peruvian farmer from Huaraz, alleges that German energy producer RWE bears partial responsibility for climate-related risks to his town.

Mr Lliuya's claim was based on various provisions under the German Civil Code, particularly section 1004 which outlines that if there is a threat of impairment, the polluter may be obliged to take measures to prevent it. Central to the case was the allegation that RWE "willingly and knowingly" contributed to climate change through its significant GHG emissions that have allegedly accelerated the melting of glaciers near Huaraz, thus increasing the volume of the glacial lake Palcacocha and placing the town at significant risk of flooding.

As a result, Mr Lliuya claimed that RWE has partially caused a dangerous situation and should contribute to the costs of adaptation measures (such as reinforcing the lake's dam) to mitigate against the effects of climate change.

Mr Lliuya was seeking proportional contribution, specifically, he sought a declaration for RWE to pay 0.47% (around €17,000) of the cost of flood protection measures for Huaraz, which corresponds to RWE's estimated share of global historic CO2 emissions at the time of filing. This figure had been based on the Carbon Majors database, which attributes historical emissions to major carbon producers.² According to the latest data, RWE ranks 44th globally and is the top coal emitter within the EU.

The court did not reject Mr Lliuya's argument that a company can be liable for its proportional contribution to a globally dispersed environmental harm resulting in localised nuisance - a novel position and a significant step for climate litigation claimants.

However, Mr Lliuya's claim failed on causation grounds, with the German court accepting the court-appointed expert's evidence that the probability of flooding in Huaraz was around 1%, calling into question the immediate threat to Mr Lliuya's home. Whilst Mr Lliuya's expert argued that Mr Katzenbach did not properly take into account the effect that future climate change would have on the rate of glacial melting. Presiding, Judge Rolf Meyer noted that the court did not "yet see" a "concrete threat to [Mr Lliuya's] property" within the next 30 years³.

Despite the adverse ruling, fundamentally the court accepted that climate impact claims can be brought under section 1004 of the German Civil Code,., even when the harm occurs across the globe and the defendant's contribution is a fraction of the total emissions.

Wider implications and related litigation

Lliuya is the first claim of its kind brought before a German court, though similar claims have been brought in the USA on tortious grounds (including nuisance) (the so-called "Carbon Majors" cases) and two other cases have been brought in Europe.

In Asmania et al. v Holcim⁴, residents of Pari Island, Indonesia, have sought compensation from cement producer Holcim in the Swiss courts for climate-related harm allegedly caused by the company's historical GHG emissions. Similarly, in Falys et al. v TotalEnergies⁵, a Belgian farmer is requesting an injunction against TotalEnergies, demanding a reduction in fossil fuel activities, with proposed penalties of €1,000,000 per month for non-compliance.

Corporate risk and the future of climate litigation in the wake of Lliuya

Establishing liability in climate impact claims remains a complex and evolving area of law. Disagreements between experts, such as those seen in Lliuya, demonstrate the evidentiary challenges plaintiffs face in establishing causation. Despite this, there is a growing momentum behind rights-based and strategic litigation aimed not only at securing compensation for harms suffered, but also at compelling systemic behavioural change within high-emitting industries through injunctive relief, court-ordered mitigation measures, and recognition of legal duties tied to climate impact.

As attribution science improves, multinationals may increasingly face claims for historical emissions, irrespective of where their operations are located. This trend is particularly relevant for insurers and legal advisors as claims increasingly addressing both historical emissions and projected future impacts, including novel theories of harm, and challenge corporate conduct.