Patrick Rey, and Jean Tirole, “Cooperation vs. Collusion: How Essentiality Shapes Co-opetition”, TSE Working Paper, n. 13-439, October 23, 2013.
The paper makes two related contributions. First, and in contrast with the rich body of literature on collusion with (mainly perfect) substitutes, it derives general results on the sustainability of tacit coordination for a class of nested demand functions that allows for the full range between perfect substitutes and perfect complements. Second, it studies the desirability of joint marketing alliances, an alternative to mergers. It shows that a combination of two informationfree regulatory requirements, mandated unbundling by the joint marketing entity and unfettered independent marketing by the firms, makes joint-marketing alliances always socially desirable, whether tacit coordination is feasible or not.