It seems that a handful of airports across Europe are currently subject of investigations by European Commission over allegations of setting lower charges for budget airlines Ryanair, Lufthansa's Germanwings and Air Berlin. Also the Commission is investigating possible illegal aid for other airports in France, Sweden, Ireland, Hungary and Romania
http://uk.reuters.com/article/2012/02/22/uk-eu-aviation-stateaid-idUKTRE81L0Q920120222
http://uk.reuters.com/article/2012/02/22/uk-eu-aviation-stateaid-idUKTRE81L0Q920120222