Study On The Short-term Impact Of Merger And Acquisition On The Market Value Of Listed Companies

In the "New Ninth Articles of the Country" issued by the State Council in 2014,listed companies are encouraged to establish a reasonable and long-term market value management mechanism.However,due to the immature market rules of China's capital market,the imperfect governance system of listed companies,the excessive "retailing" of investors and other factors,China's capital market has been in a weak and efficient state for a long time.The long-term market value of listed companies deviates greatly from its value,that is,asset prices can not correctly reflect the value,according to China Management Research.Research on the market value management performance of China's listed companies in 2017 shows that the market value management level of Listed Companies in different regions and ownership structure is quite different.It is of practical significance to adopt certain relevant measures to achieve a dynamic balance between the two.There are many ways to manage the market value of listed companies,and mergers and acquisitions not only affect the operating conditions of listed companies,but also affect the market value of listed companies,which is an important means of market value management.Based on the study of M&A behavior and market value effect of A-share listed companies in China,this paper makes a systematic study on the relationship between M&A behavior and market value fluctuation of Listed Companies in China,and provides a reference for listed companies to use M&A methods in market value management.Firstly,this paper introduces the content and means of market value management,explains the mechanism of merger and acquisition affecting market value,the background and significance of merger and acquisition.Then we study the establishment of the model and the empirical method.Then using event analysis method to make empirical analysis,this paper takes the announcement of merger and acquisition of A-share listed companies as the research object,and gets 100 samples from the database of Listed Companies in Wind financial data terminal.The data period is from January 1,2017 to December 31,2017.It takes 10 days before and after the announcement of merger and acquisition for the first time.During the observation period,we examine the impact of M&A events on market capitalization.Finally,the model results of excess market value return(AAVR)and cumulative excess market value return(CAVR)statistical T test and draw a conclusion.The results show that the M&A behavior of listed companies has obvious market value effect.It has appeared since the first day of the announcement,mainly from the announcement day to the next two days.The biggest market value effect is the first day of the first merger announcement.The sharp fluctuations in the cumulative market value effect are concentrated in the first day to 5 days after the announcement.Compared with the mainboard listed companies,the use of mergers and acquisitions in the market value management of GEM listed companies can produce greater market value effect,longer duration,better market value management effect.Cross industry M&A events have a longer and longer market effect than mergers and acquisitions in the same industry.The data show that there is no significant excess return before the announcement date,and insider trading has improved?The results of this study can provide a reference for the management of listed companies to use merger and acquisition to better understand the secondary market response to mergers and acquisitions.