Testing the superstar firm hypothesis

Firms with superior productivity, labeled superstar firms, are argued to be the link between rising concentration and fall of aggregate labor share in US. This analysis confirms that similar evidence is found within European context: market firm size increase, whereas decreases productivity. One much discussed mechanisms behind this development spreading fixed overhead costs: Highly productive firms gain share, can simultaneously spread costs over more output, thereby reducing their own aggregated industry. We show mechanism tested empirically. However, using German firm-level data, we do not find any empirical it. Our contributes ongoing debate by removing one proposed from list potential explanations for rise firms.