This study investigates whether there is any spillover uncertainty regarding a rival firm’s future operations upon a focal firm’s announcement of cybersecurity breaches and whether the existence of a chief information officer (CIO) in rival firms can reduce this spillover uncertainty. Using abnormal trading volume to capture the change in investors’ expectations, we show that compared with the focal firms, rival firms experience an increase in abnormal trading volume following the focal firm’s announcement of a security breach. The findings suggest that the spillover effect generates even more uncertainties toward these nonbreached rival firms regarding the impact of the focal firm’s security breach. However, CIOs in nonbreached rival firms can play a shielding role in mitigating such effects. Our study contributes to the literature on the impact of cybersecurity and has policy implications for encouraging a strategic perspective when managing cybersecurity risks.

本研究调查在焦点公司宣布网络安全漏洞后，竞争对手公司未来运营是否存在溢出不确定性，以及竞争对手公司中首席信息官 (CIO) 的存在是否可以减少这种溢出不确定性。使用异常交易量来捕捉投资者预期的变化，我们表明，与焦点公司相比，在焦点公司宣布安全漏洞后，竞争对手的异常交易量有所增加。研究结果表明，溢出效应对这些未违规的竞争对手公司产生了更多关于焦点公司安全漏洞的影响的不确定性。但是，未违规的竞争对手公司的 CIO 可以在减轻此类影响方面发挥保护作用。