German potato processors Bohmer and Kuhn have been fined €13.2 million (£11.63m) for price fixing.
The Bundeskartellamt, Germany’s authority for protecting competition, fined the two potato and onion packers for collusion on supply to the Metro retail group.
Proceedings against the companies began in May 2013 with a sector-wide dawn raid. Proceedings against other potato and onion packaging companies suspected of price-fixing in their supply to other food retailers were dropped for ‘discretionary reasons’.
Since the investigation carried out by the Bundeskartellamt the companies have ended the practices.
Between 2005 and May 2013, when the proceedings against the companies began, the companies were in regular telephone contact with one another about their raw product prices, particularly in the run-up to the weekly offer for packed potatoes and onions.
The two companies were the main suppliers to the Metro group for packaged potatoes and onions and their activities included purchasing raw product, washing, sorting, packing and selling to retailers.
Bohmer was one of the two largest potato and onion packers the country, with Kuhn active in southwestern Germany.
During the calls, the company representatives discussed their purchase prices for the potatoes and onions and agreed to use the same raw product price as the basis to offer prices to Metro.
Andreas Mundt, president of the Bundeskartellamt, said: "For years the companies concerned have agreed on an important parameter in the calculation of their weekly offers to Metro.
“By aligning their purchase prices used in the calculation, the two major suppliers of the Metro group virtually eliminated any price competition between them.”
The fines imposed were not yet final, with appeals able to be lodged against the decision to the Düsseldorf Higher Regional Court.