Intruder Alert? How Stock Markets React to Potential IT Security Breaches: The Case of OpenSSL Heartbleed

This exploratory study investigates how potential information technology security breaches affect stock prices. Previous research indicates that stock markets tend to punish firms that experience unsolicited disclosure of information and proprietary data. However, little research exists on the question of whether firms are punished for creating the mere potential for data theft. Based on the information boundary theory, we design our exploratory research model. Subsequently, we utilize a sample of 4,147 stocks of firms headquartered in 43 countries to conduct multiple event studies. We reveal a delayed adverse stock market response to potential IT security breaches as well as a discrimination among firms operating in different industries. Consequently, this work enhances the understanding of the full economic impact of information security measures by shedding light on previously neglected hidden costs