Voluntary disclosures, like those issued by managers in quarterly earnings calls, inform investment decisions across financial markets. They can buoy—or puncture—corporate valuations and stock prices. But it isn’t always clear what effects result from the policies governing these disclosures, especially when it comes to rules about half-truths and the duty to update.

In a new article in Management Science, Anne Beyer, a professor of accounting at Stanford Graduate School of Business, and Ronald Dye, of Northwestern’s Kellogg School of Management, use static and dynamic models to understand the effects of regulation on both voluntary corporate disclosure policies and the investors who depend on them.

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