We provide an incomplete information bargaining framework that captures the effects of differential bargaining power in markets with multiple buyers and multiple suppliers. The market is modeled as a mechanism that maximizes the expected weighted welfare of the firms, subject to the constraints of incentive compatibility, individual rationality, and no deficit. We show that, in this model, there is no basis for the presumption that vertical integration increases equally weighted social surplus, while it is possible that horizontal mergers that appropriately change bargaining weights increase social surplus. Moreover, efficient bargaining implies that in equilibrium noncontractible investments are efficient. (JEL C78, D82, D83, G34, K21, L22, L40)

中文翻译：

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不完整的信息讨价还价与合并、投资和垂直整合的应用

我们提供了一个不完整的信息讨价还价框架，该框架捕捉了具有多个买家和多个供应商的市场中不同议价能力的影响。市场被建模为一种使公司的预期加权福利最大化的机制，受激励相容性、个体理性和无赤字的约束。我们表明，在这个模型中，纵向整合增加同等权重的社会剩余的假设是没有根据的，而适当改变议价权重的横向合并有可能增加社会剩余。此外，有效的讨价还价意味着在均衡时不可收缩的投资是有效的。(JEL C78、D82、D83、G34、K21、L22、L40)