Partial portfolio disclosure, investors’ attention, and window dressing

I show that the disclosure of mutual funds’ holdings significantly affects investors’ investment decisions. As most mutual fund websites, advertisements, and fund-trading platforms only disclose a fund’s 10 largest holdings (top-10), this study finds that investors disproportionately focus on these stocks. However, this bias does not lead to additional profit because relative to their peers, funds with good top-10 performance tend to generate poor long-term returns. I design a clean and innovative discontinuity test between the performance of the 10th and 11th portfolio holdings to examine such window dressing behavior. I find that relative to their peers, funds that are small, new, and highly active are more likely to window dress and incur greater costs if they suffer from severe capital outflows. My findings suggest that partial disclosure misleads investors and allows effective window dressing.