We model competition between two firms in a vertical upstream-downstream relationship. Each firm can pay a sunk cost to enter the other's market. For equilibria in which both firms enter, the downstream price can be lower than the joint profit maximizing level, and coordination (e.g., through...

We analyze mergers and entry in a differentiated products oligopoly model of price competition. Any merger that does not yield efficiencies is unprofitable if it induces entry sufficient to preserve pre-merger consumer surplus. Thus, mergers occur in equilibrium only if barriers limit entry....