merger between regulated firms when cost synergies are uncertain before the merger and their realization becomes private … information of the merged firm. The optimal merger policy trades off potential cost savings against regulatory distortions from … market induces a more lenient merger policy. The regulated firms' diversification into a competitive segment of the market …

We analyze the optimal policy of an antitrust authority towards horizontal mergers when merger proposals are endogenous … seeks to maximize expected consumer surplus involves discriminating between mergers based on a naive computation of the post-merger … Herfindahl index (over and above the apparent effect of the proposed merger on consumer surplus). We show that the antitrust …