We propose a general framework to assess merger policy effectiveness based on standard oligopoly theory and stock market reactions. We focus on four different dimensions of effectiveness: 1) legal certainty, 2) decision errors, 3) reversion of anti-competitive rents, and 4) deterrence. We apply...

This paper analyzes the effects of mergers and acquisitions on the markups of non-merging rival firms across a broad set of industries. We exploit expert market definitions from the European Commission's merger decisions to identify relevant competitors in narrowly defined product markets....

This paper applies an intuitive approach based on stock market data to a unique dataset of large concentrations during the period 1990-2002 to assess the effectiveness of European merger control. The basic idea is to relate announcement and decision abnormal returns. Under a set of four...