We analyze the optimal dynamic policy of an antitrust authority towards horizontal mergers when merger proposals are endogenous and occur over time. Approving a currently proposed merger will affect the profitability and welfare effects of potential future mergers, the characteristics of which...

Standard welfare analysis of horizontal mergers usually refers to two effects: the anticompetitive market power effect reduces welfare by enabling firms to charge prices above marginal costs, whereas the procompetitive efficiency effect increases welfare by reducing the costs of production...