Illinois Attorney General Lisa Madigan has filed a lawsuit against four ice companies that allegedly agreed not to compete against each other. The suit claims that the four packaged ice manufacturers — Lang Ice Co., Home City Ice, Sisler’s Dairy and Products Inc. and Tinley Ice Company — made deals to divvy up markets, trade customers and share price information in central and northern Illinois.

The deals violate Illinois’ Antitrust Act, said Madigan.

“Consumers suffered when retailers were forced to pay higher prices for ice and passed on that increased cost to consumers,” Madigan stated in the complaint.

The companies manufacture and deliver packaged ice directly to consumers, businesses, government entities and groups for special events.

The alleged conspiracy began in January 2003 when Crystal Clear Ice, a large ice manufacturer and distributor in the Chicago area, went out of business and referred all of its customers to Home City Ice, according to the suit.

Home City Ice then split the customers based on their location and yearly sales revenue with its remaining competitors in the Chicago area.

“This method ensured that each co-conspirator could get an equal share of the ‘Good, Bad, and Ugly’ accounts,” Madigan stated in the complaint.

The companies further agreed to not solicit each other’s customers, and tried to discourage customers from switching suppliers by giving them false information or denying service.

In July of 2007, the Federal Bureau of Investigation raided Home City’s offices as a result of an investigation into its non-compete practices with ice companies, according to the suit.

Madigan is seeking an injunction against the illegal conduct, civil penalties, damages for overcharges on behalf of the state and fees and costs of the investigation and litigation.

Lang Ice Co. declined to comment. Home City Ice, Sisler’s Dairy and Products Inc. and Tinley Ice Company couldn’t be immediately reached.