The impact of horizontal mergers and acquisitions in price competition models

The question of what impact mergers and acquisitions have on key equilibrium performance measures is fundamental to our understanding of competitive dynamics in an oligopolistic industry. We address these questions in the context of price competition models with differentiated goods and asymmetric firms allowing for general non-linear demand and cost functions merely assuming that both the preand post-merger competition games are supermodular along with two minor technical conditions. We show that, in the absence of cost synergies, post-merger equilibrium prices exceed their pre-merger levels. Moreover, the post-merger equilibrium profit of the merged firms exceeds the aggregate of the pre-merger equilibrium profits of the merging firms. The equilibrium profit of the non-merging firms increases as well. We establish our results, at first, for settings where each firm in the industry offers a single product; we then generalize them to industries with multi-product firms. We also derive conditions under which cost synergies, by themselves, result in lower equilibrium prices than otherwise obvserve post-merger, and discuss how the combined effect of increased market concentration and cost synergies can be assessed efficiently.