We analyze a sample of 330 firms making unaudited disclosures required by Section 302 and 383 firms making audited disclosures required by Section 404 of the Sarbanes-Oxley Act. We find that Section 302 disclosures are associated with negative announcement abnormal returns of −1.8 percent, and that firms experience an abnormal increase in equity cost of capital of 68 basis points. We conclude that Section 302 disclosures are informative and point to lower credibility of disclosing firms' financial reporting. In contrast, we find that Section 404 disclosures have no noticeable impact on stock prices or firms' cost of capital. Further, we find that auditor quality attenuates the negative response to Section 302 disclosures and that accelerated filers—larger firms required to file under Section 404—have significantly less negative returns (−1.10 percent) than non-accelerated filers (−4.22 percent). The findings have implications for the debate about whether to implement a scaled securities regulation system for smaller public companies: material weakness disclosures are more informative for smaller firms that likely have higher pre-disclosure information uncertainty.

We find that equity returns associated with credit risk changes are attenuated by the debt value effect of the credit risk changes, as Merton (1974) predicts. We find that the relation between credit risk changes and equity returns is significantly less negative for firms with more debt—controlling for asset value changes, credit risk increases (decreases) are associated with equity value increases (decreases). This result obtains across credit risk levels. The relation is associated with changes in both expected cash flows and systematic risk, as reflected in analyst earnings forecasts and equity cost of capital. By inverting the Merton (1974) model, we provide descriptive evidence that if unrecognized debt value changes were recognized in income, but not unrecognized asset value changes, most credit upgrade (downgrade) firms would recognize lower (higher) income. These potentially counterintuitive income effects primarily are attributable to incomplete recognition of contemporaneous asset value changes. However, for a substantial majority of downgrade firms we find that recognized asset write-downs exceed unrecognized gains from debt value decreases. This mitigates concerns that income effects from recognizing changes in debt values would be anomalous for such firms.