Originally Posted by
Fabo.sk
Fare construction is the airlines problem to solve though. If you have a ticket that says multi city Lisbon to Geneva to Zurich, then you have a right to be flown Lisbon to Geneva to Zurich because that's what you purchased. As opposed to when you purchase a Lisbon to Zurich ticket, which just happens to include a transfer in Geneva.
Yes, that is contract Law, what you purchased & nothing to do with EU261 , you should receive exactly what the original ticket & therefore the contract shows.