Chocolate is delicious; price-fixing, a little less so. Now Canada, along with plaintiffs in the U.S., has the bitter taste of price-fixing in its mouth, and is accusing chocolate makers of collusion.

On June 6, Canada's Competition Bureau filed formal charges against Nestle Canada and Mars Canada, accusing the companies of a conspiracy to fix the price of their chocolate candies in Canada. In a separate case, the bureau anticipates that Hershey Co.'s Canadian unit will plead guilty to one count of price-fixing, Thomson Reuters reports.

Stateside, the U.S. units of Hershey, Nestle SA and Mars Inc. are facing multidistrict litigation from chocolate purchasers and individual plaintiffs accusing them of price-fixing. After it came to light in 2008 that the Canadian antitrust authorities were investigating the candy companies, plaintiffs claimed that price increases in the U.S. were made possible by the Canadian units' collusion. Canada's latest attack against the chocolate makers may well bolster the U.S. case.

Nestle and Mars' Canadian units have stated they intend to “vigorously defend” against the accusations.

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