RealPage sued by DOJ for allegedly aiding landlords in maintaining high rents.

• RealPage, a software company, was accused by the Department of Justice of illegally conspiring to weaken competition among landlords and establish a monopoly that harms millions of renters.
• The Justice Department accused RealPage of manipulating, distorting, and subverting market forces in a federal civil antitrust lawsuit.
• Merrick Garland, the Attorney General, stated, "It's widely known that rent is excessively high, and we claim this is a contributing factor."

On Friday, the Department of Justice and eight states accused RealPage of illegally conspiring to weaken competition among landlords and establish a monopoly that harms millions of renters.

The Justice Department accused RealPage of enabling landlords to manipulate, distort, and subvert market forces in a civil complaint filed in U.S. District Court in North Carolina.

The antitrust lawsuit stated that RealPage is an algorithmic intermediary that gathers, merges, and utilizes landlords' confidential information to gain a competitive advantage.

The DOJ claimed that by doing so, it benefits compliant landlords at the expense of renters who pay high prices and honest businesses that would otherwise compete.

In a press conference on Friday morning, Attorney General Merrick Garland stated bluntly, "The rent is too high, and we claim it's one of the reasons for this."

The lawsuit is the first time the government has accused a company of using mathematical algorithms to intentionally undermine the principles of fair competition in the marketplace.

Garland stated that antitrust law does not become outdated just because competitors discover new ways to engage in unlawful coordination.

"Americans should not be required to pay higher rent due to landlords' illegal schemes with companies."

The lawsuit filed by the DOJ is supported by the attorneys general of North Carolina, California, Colorado, Connecticut, Minnesota, Oregon, Tennessee, and Washington.

This is breaking news. Please check back for updates.

— CNBC's Eamon Javers contributed to this report.