Coordinated effects are merger-related harms that arise because a subset of postmerger firms modify their conduct to limit competition among themselves, particularly in ways other than explicit collusion. We provide a measure of the risk of such conduct by examining the individual rationality of participation by subsets of firms in market allocation schemes. This measure of risk for coordinated effects distinguishes markets that are at risk from those that are not and distinguishes mergers that increase risk from those that do not. A market’s risk for market allocation by a subset of firms varies with the degree of outside competition, symmetry and strength of the subset of firms, buyers’ power, and vertical integration. We make precise the widely used but rarely rigorously defined notion of a maverick firm and provide foundations for a maverick-based approach to coordinated effects. In addition, we identify previously unrecognized trade-offs between unilateral and coordinated effects.

中文翻译：

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并购审查中的协同效应

协同效应是与合并相关的损害，因为一部分合并后的公司修改了他们的行为以限制它们之间的竞争，特别是以非明确共谋的方式。我们通过检查公司子集参与市场分配计划的个人理性来衡量这种行为的风险。这种协调效应的风险度量将有风险的市场与没有风险的市场区分开来，并将增加风险的合并与没有风险的合并区分开来。市场对企业子集进行市场配置的风险随外部竞争程度、企业子集的对称性和强度、购买者的权力和垂直整合而变化。我们精确定义了被广泛使用但很少严格定义的特立独行公司的概念，并为基于特立独行的协调效果方法提供了基础。此外，我们确定了单边效应和协调效应之间以前未被认识到的权衡。