Royal Dutch Shell PLC, Eni SpA, Dow Chemical Co., Unipetrol AS and Trade-Stomil were fined by the EC.
Bayer AG was found guilty but was not fined because it blew the whistle on the others, according to the EC.
The EC said the group fixed pricing and shared customer information on buyers of butadiene rubber and emulsion styrene butadiene rubber used widely in tire production between 1996 and 2002.
Italy’s Eni got the largest fine at $357.6 million, and Shell was hit for $211 million. Dow Chemical, based in Michigan, was fined $84.8 million, Czech Republic’s Unipetrol was fined $23 million, and Poland’s Trade-Stomil fined $5 million.