The cascade effect: Are the U.S. economy and global stock markets vulnerable to the collapse of First Republic Bank?

Following the collapse of Silicon Valley Bank and Signature Bank, First Republic Bank collapsed and is considered the second-largest bank failure in U.S. history. These bank runs can have a cascading or contagion effect on other large banks, and U.S. banking crises can flare up again. We examine the effect of the First Republic bank run on top U.S. banks, U.S. stock indices, and global stock indices using standard event study methodology. We report abnormal returns and cumulative abnormal returns for the event day (t = May 01, 2023) and the 10-day event window (t-5 to t+5), respectively, using data from the 120-day estimation window. The results indicate that on the event day, only JP Morgan Bank's returns were negative, while other banks acted as safe havens for investors. No significant change in returns on the event day is observed for U.S. sector indices (except for the healthcare sector) and global stock exchanges, except for the European and Chinese markets. During the event window, the occurrence of the event significantly affects bank returns after the event date, but no significant effect is found before the event date. Similarly, the healthcare and transportation sectors are more affected than other sectors, while the U.S. and Canadian stock markets seem to be more susceptible to the bank run. Overall, the results suggest that the U.S. government should take decisive initiatives to stop the ripple effect and protect the entire financial system.