If IAG were successful in a bid for Aer Lingus, there would be a referral to the competition authorities, who would analyse the deal on a route-by-route basis. DUB-LHR is currently an EI/BA duopoly and would fall to a monopoly, so one would expect that the price of approval for a deal would be the surrender of a package of slots in DUB and LHR to allow a competitor to enter that route. Who would a credible competitor be? Easyjet? Eurowings? Little Red operated by Aer Lingus? (that last one is a joke, by the way
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