Ways to measuring public attention are important questions, and many researchers use indirect measures to capture investors’ attention such as trading volume (Hou et al., 2008), extreme returns (Barber and Odean, 2008), and news and headlines (Yuan, 2008). On this research, we use Google search volume index which provides a direct measure to detect people’s interest. Using M&A data of the United States, we investigate the causality over search volume query changes on takeover returns. We find abnormal trends in Google search volume index such as volume reaching the spike before the mergers announcements. We present that earlier search volume hits the spike, more outperforming on both acquirer and target sides. We further believe that our research can contribute to the academia as a novel method to detect possible information leakage problem.

Keywords: Google trends, M&A rumor, long-term performance, abnormal return