German Supreme Court (BGH) in today’s judgment Xa ZR 5/09 decided that airlines must not declare a ticket void if the flight coupons are not used in their correct order. Such provisions are widely used in general conditions of contract of several airlines to prevent passengers from booking flight segments which they actually don’t want to use in order to benefit from a lower price.In the particular case the German Federal Consumer Protection Association (Bundesverband der Verbraucherzentralen) had sued British Airways and Lufthansa to cease and desist from using such provisions.BGH acknowledged a legitimate interest of the airlines to avoid evasions of their tariff systems; this purpose, however, could also be achieved by milder means as for instance a surcharge for not having used a coupon for a flight segment. To completely ban the passenger from further contractual services would be disproportionate and against the principle of good faith as the provisions at stake made no distinction on whether the passenger deliberately booked more segments than required or left coupons unused for justified reasons.Source: BGH press release 91/2010; full text available in German here>>.