We present a model of investing based on environmental, social, and governance (ESG) criteria. In equilibrium, green assets have negative CAPM alphas, whereas brown assets have positive alphas. Green assets' negative alphas stem from investors' preference for green holdings and from green...

We empirically analyze the nature of returns to scale in active mutual fund management. We find strong evidence of decreasing returns at the industry level: As the size of the active mutual fund industry increases, a fund's ability to outperform passive benchmarks declines. At the fund level,...

We study tradeoffs among active mutual funds' characteristics. In both our equilibrium model and the data, funds with larger size, lower expense ratio, and higher turnover hold more-liquid portfolios. Portfolio liquidity, a concept introduced here, depends not only on the liquidity of the...