U.S. academic discourse on director interlocks is not new. Yet, the increased attention to common ownership has also brought to light the increased tendency of interlocked directors to serve in the same industry. I termed these directors as horizontal directors in my earlier work—shining a light on the benefits they bring to investors and companies but also the risks they pose to governance and antitrust law. This article revisits the prevalence of horizontal directors armed with six additional years of data and shows that the prevalence of horizontal directors has remained steady, even as attention to common ownership has increased in recent years. These findings should serve as a clarion call to regulators—urging them to directly address horizontal directors.

中文翻译：

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重新审视横向董事

美国关于董事联锁的学术讨论并不新鲜。然而，对共同所有制的日益关注也揭示了连锁董事在同一行业服务的趋势增加。在我之前的工作中，我将这些董事称为横向董事——阐明了他们为投资者和公司带来的好处，以及他们对治理和反垄断法构成的风险。本文借助另外六年的数据重新审视了横向董事的普遍性，并表明横向董事的普遍性保持稳定，尽管近年来对共同所有权的关注有所增加。这些发现应该成为监管机构的号角——敦促他们直接解决横向董事问题。