When is upstream collusion profitable?
受日本汽车零部件供应商合谋案启发，研究上游企业合谋提高中间品价格后补偿下游企业仍能盈利的条件，发现合谋价格若能更好平衡纵向与横向外部性，则能提升两行业总利润。
Abstract Motivated by the recent antitrust cases in which Japanese auto parts suppliers colluded to raise supply prices against their long‐term collaborators, the Japanese carmakers, we study the conditions under which an upstream collusion is profitable even after compensating downstream direct purchasers. Oligopoly competition in successive industries is shown to give rise to a vertical externality and a horizontal externality. If a collusive price of intermediate goods better balances the two externalities, the collusion will raise the joint profit of all firms in the two industries and is therefore profitable for the upstream after compensation of downstream firms.