Vertical mergers have attracted much attention in recent years. We assess the role of presumptions and likelihoods in vertical merger analysis and guidelines. We focus in particular on the role that we believe statistical evidence in general—and retrospective analyses more specifically—should play in determining presumptions. We also discuss how horizontal merger guidelines provide frameworks to analyze the horizontal issues that can be associated with vertical mergers. We conclude that while some vertical mergers may raise concerns, the evidence at this point does not provide sufficient guidance to develop presumptions that are related to strictly vertical issues.

近年来，纵向并购备受关注。我们评估了假设和可能性在纵向合并分析和指南中的作用。我们特别关注我们认为一般统计证据——更具体地说是回顾性分析——在确定推定中应该发挥的作用。我们还讨论了横向合并指南如何提供框架来分析与纵向合并相关的横向问题。我们得出的结论是，虽然一些纵向合并可能会引起关注，但此时的证据并没有为制定与严格纵向问题相关的假设提供足够的指导。