Mirror Voting

We provide the first large-scale empirical evidence assessing proposed reforms to corporate voting. We focus on "mirror voting," meaning pro-rata voting by indexed shareholders based on the proportion of votes cast by non-indexed shareholders. We find that if index funds had followed "mirror voting" for more than 600,000 agenda items from 2005 through 2025, the results would have flipped just 12 times, compared to thousands of flips if index funds had voted based on proxy advisor or management recommendations. We examine "mirror voting" flips and find that they tend to involve contentious votes. We also find that if index funds had abstained from voting, one in ten shareholder meetings would have been below the quorum threshold. Based on our results, we conclude that a "mirror voting" rule for index funds would have been the least disruptive of several reforms historically. We argue that this evidence should be considered in the analysis of the benefits and costs of proposed voting reforms.