Good to know...!
from Jürgen Vogl
However, the regulation leaves open how the reimbursement of the ticket price on multi-segment flights is to be calculated - i.e. whether in this case only the price for the segment on which a passenger was downgraded must be used for the calculation or the entire route until the final destination is reached.
In the case we would like to present to you today, Case C-255/15 "Mennens", a passenger had booked a flight on the routes Düsseldorf-Dubai and Dubai-Tokyo (both in First Class) as well as Singapore-Dubai and Dubai-Frankfurt (both in Business Class). On the first leg (Düsseldorf-Dubai), he was not transported in First Class but in Business Class, whereupon he demanded a refund of 75 percent of the airfare for the entire trip (return) including taxes and fees from the airline.
However, the airline only refunded 75 percent of the pro rata fare for the affected leg of the flight (which covered more than 3,500 kilometers), excluding taxes and fees. As the airline and the passenger were unable to reach an agreement, the case went to court and was subsequently referred to the European Court of Justice (ECJ) for a ruling, as the court seised recognized a fundamental question of European law that had to be answered by the ECJ. The ECJ ruled that the airline only had to reimburse the proportionate price for the affected leg of the journey - in our case for the route between Düsseldorf and Dubai. Taxes and fees do not have to be reimbursed as long as they do not depend on the booking class.