This paper studies how common institutional ownership (CIO) affects information diffusion in the stock market. My findings suggest that CIO can exacerbate the slow spread of information across firms. With over 50% of institutional investors holding concentrated stock portfolios, I infer a fundamental connection among firms with CIO. These firms exhibit cross-predictability in monthly stock returns, leading to a CIO-based peer momentum strategy that outperforms 's () shared-analyst momentum strategy. This anomaly stems primarily from institutional investors with fewer stock holdings, who employ passive asset management characterized by lower portfolio turnover and more delegated investment.

中文翻译：

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信息在共同拥有的公司中逐渐传播

本文研究共同机构所有权（CIO）如何影响股票市场的信息传播。我的研究结果表明，首席信息官可能会加剧企业间信息传播的缓慢。由于超过 50% 的机构投资者持有集中的股票投资组合，我推断公司与 CIO 之间存在根本联系。这些公司在每月股票回报方面表现出交叉可预测性，从而导致基于 CIO 的同行动量策略优于 () 共享分析师动量策略。这种异常现象主要源于持有较少股票的机构投资者，他们采用被动资产管理，其特点是投资组合周转率较低和委托投资较多。