In 2013, the stock prices of U.S. acquiring companies rose 4%, on average, from the day before a deal was announced until the day after announcement, according to Dealogic. In 2014, they rose 3%, and so far this year, nearly 4%. Between 2008 and 2011, the average acquiring company’s stock dropped.
These stats refer to all industries in the aggregate and to deals of some unstated minimum size.
“The efficient-market hypothesis may be the foremost piece of B.S. ever promulgated in any area of human knowledge!”