The European Union's anti-trust watchdog has fined Sony, Panasonic and Sanyo for price fixing in the market for batteries used in laptops and mobile phones.
The European Commission, which polices competition issues in the EU, fined the three a total of 166 million euros ($176 million) for breaking antitrust rules along with Samsung SDI.
Samsung SDI avoided a fine because it blew the whistle on the cartel.
EU Competition Commission Margrethe Vestager said in a statement Monday that collusion among the four "affected the prices of a number of goods sold to European consumers."
A Commission probe found the companies met together over more than four years, often in Asia, to plan ways to avoid aggressive competition in the rechargeable lithium-ion battery market.
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