DUH v. Deutsche Lufthansa AG

German Environmental Action (Deutsche Umwelthilfe, DUH) brought an action against Deutsche Lufthansa AG in the Regional Court of Cologne (Landgericht Köln), concerning the advertising for the use of Sustainable Aviation Fuels (SAF), which Lufthansa advertised that passengers could “reduce their flight-related CO₂ emissions directly during booking through the use of sustainable aviation fuels (SAF).” The plaintiff also challenged the advertising of the option to offset flight emissions through contributions to climate protection projects.

On March 21, 2025, the Regional Court ruled in favor of the Plaintiff, prohibiting both practices. The court found the SAF advertisement misleading, as it could falsely lead consumers to believe their purchase would directly apply to and reduce emissions of their specific booked flight. Regarding the option to offset flight emissions, the court found that the scope and mechanics of the promised emission reduction were left ambiguous.

On July 8, 2026, the Higher Regional Court of Cologne (Oberlandesgericht Köln) partially upheld the lower court’s decision, also prohibiting Lufthansa on their advertisement on SAF. (The claim on climate protection projects was withdrawn by the Plaintiff.) The court found the statement misleading because consumers were not informed with sufficient clarity about when the SAF would actually be used, which was within six months of the purchase. The court considered the timing of the emissions-reduction measure to be material information for environmentally conscious consumers. The possibility that the passenger could make their particular flight more environmentally friendly through the physical use of SAF was an important reason for paying the additional charge. The information was only available at a later stage, including in FAQs on a separate level of the website, and was therefore insufficient.

The court did not, however, accept all of DUH's broader arguments concerning Lufthansa's duty to disclose the full range of climate impacts associated with aviation, including non-CO₂ effects such as contrails and nitrogen oxides. The decision therefore represents a partial success for DUH.