Cushman & Wakefield was among six large landlords sued by the U.S. Department of Justice over alleged anticompetitive practices in housing rental markets, the DOJ said on Tuesday.

The Justice Department is thrusting the largest rental property managers into the spotlight as it expands a price-fixing lawsuit alleging widespread collusion in the housing rental market.

Six of the country’s most powerful landlords were named in a lawsuit brought forth by the U.S. Justice Department. Blackstone, Cushman & Wakefield, Greystar, Camden, Pinnacle, Willow Bridge, and Cortland were all implicated.