Permalink : http://hdl.handle.net/2115/5377

KEYWORDS : Anti-Monopoly Law, Price Leadership, Conscious Parallelism

The Japanese Anti-monopoly Law [Article 18-2] includes a price increase reporting system to oversee conscious parallelism or price leadership in an oligopoly market. We examined the relationship between exchange of price increase information (announcement, practice dates, and increase ratio) and conscious parallelism in Japanese manufacturing industries. We have reached the following conclusions: The leading company took a leadership role in announcement and practice dates and then the subordinate company coordinated or followed soon after the leading one. Examining the difference between the announcement date and the practice date, the subordinate company's difference was smaller than the leading one's. Furthermore, when the subordinate company led an announcement date, it also led the practice date. In many cases the subordinate company's increase ratios were larger than the leading company's. That is to say, the leading company took a leadership role on the announcement date, but the companies that actually necessitated the price increase were the subordinate companies rather than the leading one. We suggest that the anti-trust authority collects the report of minimum profit rate as a reason for price increase in order to make the regulation effective. (JEL K21, L41, L52)