Nine auto parts makers -- Tokai Rika, Autoliv, TRW Deutschland Holding GmbH, Nippon Seiki Co., Fujikura Ltd., Furukawa Electric Co., Denso Corp., Yazaki Corp. and G.S. Electech -- have pleaded guilty.
The U.S. Justice Department is working with antitrust officials in Japan and Europe on the probe. It initially confirmed it was conducting a price-fixing investigation in February 2010 and has imposed $809 million in fines to date, including $470 million against Yazaki, Hammond said during a speech to the State Bar of Michigan.
Twelve people have pleaded guilty and 10, all from Japan, have surrendered to U.S. jurisdiction and are serving jail terms of one to two years, he said.
"It's still very much ongoing, but it already appears to be the biggest criminal antitrust investigation that we've ever encountered," Hammond said. "I say (it is) the biggest with respect to the impact on U.S. business and consumers, and the number of companies and executives that are subject to the investigation."