set of industries. We exploit expert market definitions from the European Commission's merger decisions to identify … particularly pronounced in markets with few players, high initial markups and concentration. We also provide evidence that merger … rivals reduce their employment, sales and investment, while their profits increase around the time of a merger. …

data from the European Commission’s market assessments in merger decisions with production data, we use recent … the performance of almost 600 rival firms in close to 200 merger cases before and after the change in market structure … increase their markups in the years after a merger. The effects are concentrated in markets with few competitors, among firms …