Common ownership exists when investors concurrently hold partial and significant shares in related firms. In this paper, I compile, document, and taxonomize 30 separate cases of intervention to demonstrate how common owners influence firm behavior. Although previous literature has identified a link between common ownership and product market outcomes, critics have questioned a common owner’s ability and incentive to alter the behavior of portfolio firms. Missing from the debate are observable interventions from common owners and the mechanisms through which common owners exercise their influence. This paper compiles relevant case studies from media coverage, regulatory proceedings, policy groups, and annual stewardship reports to uncover these channels.

中文翻译：

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共同所有者的干预

当投资者同时持有相关公司的部分和重要股份时，就存在共同所有权。在本文中，我汇编、记录和分类了 30 个不同的干预案例，以展示共同所有者如何影响公司行为。尽管以前的文献已经确定了共同所有权和产品市场结果之间的联系，但批评者质疑共同所有者改变投资组合公司行为的能力和动机。辩论中缺少可观察到的共同所有者的干预措施以及共同所有者行使影响力的机制。本文汇编了来自媒体报道、监管程序、政策组和年度管理报告的相关案例研究，以揭示这些渠道。