Market reactions to publicly announced privacy and security breaches suffered by companies listed on the United States stock exchanges: A comparative empirical investigation

Using a sample of security and privacy breaches the present research examines the comparative announcement impact between the two types of events. The first part of the dissertation analyzes the impact of publicly announced security and privacy breaches on abnormal stock returns, the change in firm risk, and abnormal trading volume are measured. The second part of the dissertation analyzes differential impact between security and privacy breaches on abnormal stock returns, the change in firm risk, and abnormal trading volume are measured.;Using a sample of 114 security (65) and privacy (49) breaches on average, security breaches resulted in more negative abnormal stock returns than do privacy breaches. While firm risk for privacy events does not change appreciably, firms experiencing security events show a significant increase in risk. The risk shifts between the security and privacy breaches is significantly different. Firms that announced a security or privacy breaches experienced abnormal trading volume.