CHICAGO (Legal Newsline) - Illinois Attorney General Lisa Madigan announced on Tuesday that she has proposed a consent decree to require Dean Foods to sell a milk processing plant in Waukesha, Wis.

Madigan was joined by the Wisconsin Attorney General J.B. Van Hollen and the U.S. Department of Justice in filing the proposed consent decree.

The Dallas-based Dean Foods is the United State's largest processor and distributor of milk and other dairy products. It purchased the Waukesha plant from Foremost Farms, giving it more than 60 percent of the fluid milk sales in northeastern Illinois.

A federal lawsuit against Dean Foods was filed last year due to the company's ownership of the plant, which raised antitrust concerns. It was alleged that its ownership could affect milk prices throughout the northeastern part of Illinois.

The suit alleged that Dean Foods deprived retailers of the benefits of substantial head-to-head competition between Dean Foods and Foremost Farms.

Under terms of the proposed consent decree, Dean Foods must sell its milk processing plant to preserve competition in Northern Illinois.

"We are committed to protecting consumers by enforcing the antitrust laws to ensure vigorous competition," Madigan said. "Allowing Dean Foods to keep the Foremost Farms plant could have resulted in higher prices and solidified a dominant position for Dean Foods in northern Illinois. Selling the facility will contribute to increased competition and will benefit Illinois consumers."

Dean Foods, Foremost Farms and other milk processors buy raw milk from dairy farms and agricultural cooperatives to pasteurize and package. The milk is then distributed and sold to retail customers.

The decree requires the company to sell the plant to a new owner in the next 90 days. If Dean Foods fails to sell the plant in that time period, a trustee will be appointed by the court with the power to sell the plant.

Dean Foods must also notify the U.S. Department of Justice and the Illinois Attorney General at least 30 days priot to any further acquisition of a milk processing plant in Illinois or within 150 miles of its borders if the plant is valued at $3 million or more.