Dean Foods is being ordered to sell its milk processing plant in Waukesha, which settles a federal antitrust lawsuit that fought the company’s 2009 purchase of the plant from Foremost Farms USA because it controlled nearly 60 percent of milk sales, according to a news release from Attorney General J.B. Van Hollen.

“We are committed to protecting consumers by ensuring vigorous competition among milk processors,” Van Hollen said in the release. “Selling the Waukesha plant will introduce another competitor capable of serving grocery stores, convenience stores, schools and other milk retailers throughout Wisconsin.”

The lawsuit challenging the purchase was based on antitrust laws that claimed the purchase prevented retailers and school districts from benefiting from competition between the two companies, according to the release.

Dean Foods has 90 days to sell the plant or the federal court will appoint a trustee to sell the plant, the release states. The new owners will be given the rights to continue operations of the Golden Guernsey and La Vaca Bonita brands, the release states.

Dean Foods also has to notify the United States Department of Justice and the Wisconsin attorney general within 30 days of purchasing a plant worth $3 million or more in Wisconsin or within 150 miles of its borders.