Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
I examine the question whether cooperation in R&D among firms producing similar products leads to product market collusion. Suppose that firms engage in a stochastic R&D race while maintaining the collusive equilibrium in a repeated‐game framework. Innovation under non‐cooperative R&D leads to an inter‐firm asymmetry, destabilizing collusion in pre‐discovery and post‐discovery periods. Innovation sharing under cooperative R&D preserves the symmetry and also increases total profit, thereby facilitating collusion. However, welfare may increase with cooperative R&D. I also examine the condition for collusion under licensing and compare the results.