글로벌 금융위기 전후 우회상장합병과 일반합병 공시에 대한 시장효율성

Among the mergers publicly announced by the Financial Supervisory Service from July, 2006 to June, 2012, this study took samples of 302 mergers data that had the merging firm as the stock listed company and categorized it to the reverse mergers sample and the general mergers sample and used the event study methodology and analyzed the merger announcement effect and market efficiency and especially separated into terms before the global financial crisis and after the crisis and looked deeply whether there was any change in the market efficiency. Taking the corporation’s board of directors resolution date as the event date and by using the market model, the abnormal returns was measured and to test the statistical significance of the average abnormal returns and the cumulative average abnormal returns, the heteroscedasticity adjusted significance test method that modified the hypothesis test method assuming cross-sectional independence used by Brown and Warner(1985) etc. was utilized. As a result of measuring and analyzing the abnormal returns before and after the merger announcement date for the entire sample period, there was merger announcement effects for both reverse mergers and general mergers and market effectively reacted to the merger announcement information and it showed that the semi-strong form of efficient market hypothesis was established. We further categorized and analyzed the before and after period of the global financial crisis. It was found that in the case of reverse mergers, the market efficiency of the merger announcement slightly improved after the crisis than before the financial crisis and in the case of general mergers, the market reacted efficiently to the merger announcement both for the period before and after the financial crisis.