What accounts for substantial legal change? With corporate law, many think a stock market crash is key. But not all crashes lead to reform. So, what else is necessary? This paper uses a “critical junctures” model borrowed from social science to explain when and why major corporate law change happens. The model indicates that a combination of a lengthy period of depressed share prices and a perception that business wrongdoing was integrally related to the slump are required to create the window of opportunity for significant and enduring reform. It follows that the COVID-19 pandemic is unlikely to serve as a catalyst for major changes to corporate law.