Japan's Fair Trade Commission raided the offices of Asahi Breweries, Kirin Brewery, Suntory Beer and Sapporo Breweries this week on suspicion of price-fixing. The four companies collectively control more than 90% of Japan's domestic beer market.
Investigators suspect the breweries colluded to set prices for beer and other beverages, potentially forcing consumers to pay inflated prices. The practice would violate Japan's anti-monopoly law.
The Fair Trade Commission conducted the raids at the companies' offices. Media reports indicate the alleged collusion could have resulted in higher costs for drinkers across the country.
No charges have been announced. The investigation is ongoing.