Since 2011, the U.S. Department of Justice has charged two dozen Japanese auto parts companies and 32 of their employees with rigging bids or fixing the prices for their products in what it calls its largest such investigation to date.

The onslaught continued in April with charges against four executives at Tokyo-based Bridgestone Corp. The DOJ says it is not limiting its investigation to Japan, but only two non-Japanese companies and one of their employees have been charged so far.

Many of the cartels were formed in Japan and largely affected Japanese automakers, yet Attorney General Eric Holder said they "targeted U.S. manufacturing, U.S. businesses and U.S. consumers."