Do Index Funds Monitor?
研究发现，相对于主动基金，指数基金在监督公司管理层方面效果较差，包括较少反对有争议的治理问题、缺乏有效的公开或私下参与，以及导致董事会独立性降低和薪酬绩效敏感性变差。
Abstract Passively managed index funds now hold over 30$\%$ of U.S. equity fund assets; this shift raises fundamental questions about monitoring and governance. We show that, relative to active funds, index funds are less effective monitors: (a) they are less likely to vote against firm management on contentious governance issues; (b) there is no evidence they engage effectively publicly or privately; and (c) they promote less board independence and worse pay-performance sensitivity at their portfolio companies. Overall, the rise of index funds decreases the alignment of incentives between beneficial owners and firm management and shifts control from investors to managers.