PSM estimation results.

Share repurchase is not only an important financial policy of the company, but also a financial policy with a very wide range of influence. A scientific and reasonable share repurchase policy has a significant financial effect in terms of an equity structure optimization, capital structure adjustment, cash holding control, and even management compensation system design. The long-standing share repurchase in the U.K. and U.S. companies and the recent practice of share repurchase by Chinese listed companies imply an important financial proposition: share repurchase is a high-quality financial policy that, when properly applied, will help reduce the cost of capital. The data in this study show that share repurchases can reduce the level of firms’ cost of capital and play an important role in enhancing their competitiveness. This study also finds that Chinese listed companies, when formulating and implementing share repurchase programs, do not subjectively view share repurchases as a policy tool to adjust cash holdings and capital structure. In addition, they do not view share repurchases as an alternative to cash dividends but use equity incentives for management as the main intention for share repurchases. This decision-making concept is not conducive to the rational use of share repurchase policies in the long run and should be a cause for concern in the business community. Finally, the leverage and the cash holding path are the main motives affecting share repurchases and are the important fundamental mechanisms in this study, while the mediating mechanism test finds that share repurchases mainly reduce the cost of capital through two information perspectives of analyst following and stock liquidity. The heterogeneity analysis shows that the role of share repurchases in reducing the cost of capital is more obvious in enterprises with fierce product market competition, high institutional investor shareholding.

股票回购（Share Repurchase）不仅是公司的重要财务政策，亦是影响力覆盖范围极广的一类财务举措。科学合理的股票回购政策，在优化股权结构、调整资本结构、管控现金持有乃至设计管理层薪酬体系等维度，均可产生显著的财务效应。英美企业长期开展股票回购的实践，以及中国上市公司近年的股票回购操作，共同指向一项重要的财务命题：股票回购是一项高质量财务政策，若应用得当，可助力降低企业资本成本。

本研究的数据显示，股票回购能够降低企业的资本成本水平，对提升企业竞争力发挥重要作用。本研究同时发现，中国上市公司在制定与实施股票回购方案时，并未将股票回购主观地视作调整现金持有与资本结构的政策工具；此外，它们也未将股票回购作为现金股利的替代方案，而是将管理层股权激励作为开展股票回购的核心动因。这一决策理念从长期来看不利于股票回购政策的合理运用，应当引起商界的关注。

最后，杠杆水平与现金持有路径是影响股票回购的主要动因，亦是本研究的核心基础机制；而中介机制检验结果表明，股票回购主要通过分析师跟踪与股票流动性这两大信息视角降低资本成本。异质性分析显示，在产品市场竞争激烈、机构投资者持股比例较高的企业中，股票回购降低资本成本的作用更为显著。