MINNEAPOLIS (WCCO) — A class action lawsuit filed over the weekend accuses the nation’s top meatpackers — Cargill, JBS, National Beef, and Tyson — of conspiring to artificially increase the price of beef and thereby boost their profit margins.

The lawsuit, filed in Minneapolis federal court on behalf of a Chicago grocer, says that the meatpackers, which together control more than 80% of the industry, used their position to limit the supply of cattle and fix the price of beef, leading to “historically high” margins in the market.

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This scheme has been operating since at least the start of 2015, the lawsuit says, adding that one consequences of the conspiracy was a spike in beef prices during the COVID-19 pandemic.

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This spike in prices, and the shutdown of meatpacking plants across the Midwest, prompted investigations by the U.S. Department of Justice and the Department of Agriculture. The results of those investigations have yet to be fully released, although details have appeared in the press.

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Recently, other meat and fish industries have faced similar antitrust lawsuits. Just last week, the CEO of Pilgrim’s Pride, a chicken manufacturer, was indicted on charges of price fixing.