Amazon Japan was raided on the search for evidence of undue pressure to retailers that sell products on that website.
“The Japanese unit of the U.S.-based internet retailer forced conditions such as requiring retailers to sell products below the price they advertised on rival sites, the Nikkei business daily reported Monday. […] The case centered on clauses that Amazon had with publishers which may shield the company from competitors, including an obligation to be informed of more favorable terms being offered by rivals.”
This concern is similar to the one raised against Booking.com last year.
Texts form: http://www.japantimes.co.jp/news/2016/08/08/business/amazon-japan-offices-raided-antitrust-case/#.V6iis_nhCM8