As has been noted, the Yamaguchi-gumi is the largest of the three main yakuza groups in Japan. It is also the most violent and the most active in infiltrating the stock market and high finance. Extreme loyalty is demanded; anyone caught snitching on his boss may be forced to sacrifice an appendage or even be murdered. In terms of expansion and methods, it is like the Wal-Mart of organized crime. It has its own financial division and maintains strong ties with politicians, including former prime ministers.
