This paper examines when information asymmetry among investors affects the cost of capital in excess of standard risk factors. When equity markets are perfectly competitive, information asymmetry has no separate effect on the cost of capital. When markets are imperfect, information asymmetry can have a separate effect on firms’ cost of capital. Consistent with our prediction, we find that information asymmetry has a positive relation with firms’ cost of capital in excess of standard risk factors when markets are imperfect and no relation when markets approximate perfect competition. Overall, our results show that the degree of market competition is an important conditioning variable to consider when examining the relation between information asymmetry and cost of capital.

While researchers and practitioners alike estimate firms' exposures to systematic risk factors, the disclosure literature typically assumes that exposures are common knowledge. We develop a model where the firm's exposure to a factor is unknown, and analyze the effects of factor-exposure uncertainty on share price and the effects of disclosure about the exposure. We find that: (1) factor-exposure uncertainty introduces skewness and excess kurtosis in the cash flow distribution relative to the commonly used normal distribution; (2) risk-factor disclosure affects all moments of that distribution; and (3) the pricing of higher moments affects the price response of disclosure and the incentives to disclose. For example, factor-exposure uncertainty may actually increase price when the uncertainty implies positive skewness in the cash flow distribution. Hence, a reduction in uncertainty through disclosure may increase cost of capital. We also extend our model to multiple firms and show that factor-exposure uncertainty manifests as uncertainty about a firm's CAPM beta.