Spiegel Online reported Tuesday that a 100-page Federal Cartel Office document concerning the investigation indicates the price fixing that was thought to have occurred in 2006 and 2008 has gone on for as long as 20 years.
The previously reported time line was "most likely just the tip of the iceberg," the report says.
The head of the Veltins brewery Volker Kuhl said in late January that price hikes were agreed to in telephone calls and in off-agenda meetings at industry gatherings.
Often the industry's larger companies would agree on a price, then let the smaller breweries in on the changes. "Then it often came to a branch-wide beer price increase," Kuhl said.
Spiegel Online reported that the brewers could be fined hundreds of millions of dollars for the colluding on prices.
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