How Factor-Driven Fund Flows Can Create Oversized Funds and Negative Alpha

Summary

The article summarizes research on a mismatch between active equity funds’ management capacity and the assets they attract. It argues that investors often mistake returns associated with common factor exposures for evidence of manager skill. Funds with stronger past factor-related returns consequently receive more inflows, and those inflows can push assets beyond the scale at which the manager can invest efficiently.

Using US active equity mutual fund data, the underlying study estimates factor-related returns with multi-factor models, groups funds by assets and prior factor returns, and compares subsequent risk-adjusted performance. It reports that high prior factor-return funds underperform similar-sized funds and benchmarks, with larger shortfalls among funds facing higher trading costs. A stock-level analysis also links crowded styles, driven by uninformed flows, to weaker later returns. The article reports robustness checks across model and sample variations, but the evidence is historical and specific to the studied market and period. The findings motivate considering how a fund grew, alongside its current size, when evaluating it; they do not establish a universal selection rule or guarantee future results.

Key ideas

• Investors may interpret factor-driven returns as evidence of active management skill.
• Funds with high prior factor-related returns receive larger inflows, even after accounting for factor-adjusted performance.
• Within similar asset-size groups, funds whose assets grew through factor-related returns show weaker subsequent performance.
• The underperformance is more pronounced among funds with higher trading costs, consistent with decreasing returns to scale.
• Crowded investment styles associated with flow-driven buying also tend to have weaker subsequent returns.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.