M & A Activity Measurement Methods And Evidence, The Operating Performance Of Listed Companies

After China joined the World Trade Organization (WTO), domestic enterprises would face keen competition. For meeting the challenge, more and more companies place hope on Merger and Acquisition, one outside grow-up way, to rapidly promote their key competitive power and occupation rate of market, among them the listed company is the most active particularly. According to the statistics, there has been more than 220 times of "M&A" in the security market during the 2002 alone. With "M&A" more and more becoming the strategic means of company's capital operation and self-development, people generally pay close attention to the synergy of "M&A".Though the domestic and international scholars have done a large amount of positive research to this problem, but there is not a unified conclusion all the time. Generally speaking, the domestic scholar relatively lays particular emphasis on studying the operation performance of "M&A" through the inspection of the financial index of listed company, and there is still relatively few systematic positive research about the influence to the stock price. This text regards the "M&A" incidents that have happened during 2001 and 2002 in the security market of our country as samples to study the synergy of the "M&A".The article introduces some relevant concepts and theory about "M&A", and reviews the "M&A" course over the years of China security market and the documents about the synergy of "M&A". Then the text carries on positive analysis to the chosen sample, and study the average abnormal changing value and accumulate abnormal changing value of the sample in the announcement day, the 30 days before the announcement day and the 30 days after the announcement day .At last the text study the accumulating abnormal value of the stock price in the immediate time, a short time and the middle time in order to observe the impact onthe stock price of "M&A". Through the analysis to the result of empirical study, the text gets two conclusions:l.The declaration of "M&A" of the listed company has remarkable positive influence on shareholder's wealth.2.The inside trade problem of security market is improved notably.Finally, propose some suggestions to the listed company on the issue that how to maximize shareholder's wealth while merging, and provide some advise on stub trade to investor.