Adds RealPage comment, paragraph 7-8

By Jonathan Stempel

April 23 (Reuters) - New Jersey sued the property management software company RealPage, accusing it and 10 of the state's largest landlords of conspiring to drive up residential rents, violating federal and state antitrust laws and New Jersey consumer fraud laws.

The complaint filed on Wednesday by state Attorney General Matthew Platkin said the defendants, including AvalonBay Communities AVB.N, illegally used RealPage's revenue management software and algorithms to inflate rents for apartments in multifamily properties.

New Jersey said the defendants also quietly exchanged non-public data such as lease prices, amenities, concessions offered, property values and housing inventory, in order to align pricing and avoid competition to lower rents.

The state said the collusion has inflated rents for hundreds of thousands of residents, with half of low-income renters paying more than 30% of their gross incomes toward rent. Many real estate and financial experts recommend a 30% limit.

"This lawsuit is about putting a stop to corporate greed at its worst," said Jeremy Hollander, acting director of New Jersey's division of consumer affairs. "The housing market in New Jersey is already stacked in favor of landlords but the defendants wanted more."

RealPage, based in Richardson, Texas, has said its pricing software sometimes recommends lowering rents instead of raising rents, and leaves decision making to landlords.

A spokeswoman, Jennifer Bowcock, added that the software is designed to comply with housing laws.

"The claims brought by the New Jersey attorney general are devoid of merit and will do nothing to make housing more affordable," Bowcock said in an email. "New Jersey should stop scapegoating pro-competitive technology."

AvalonBay, based in Arlington, Virginia, did not immediately respond to requests for comment.

The lawsuit seeks an injunction, civil penalties, the recouping of illegal profit and the appointment of a monitor to prevent more wrongdoing.

New Jersey sued eight months after the U.S. Department of Justice and eight other states also sued RealPage over its algorithms.

On April 2, RealPage sued the city of Berkeley, California, calling an ordinance against using algorithms to set rents an unconstitutional restriction on content-based speech, violating the First Amendment.

The case is Platkin et al v RealPage Inc, U.S. District Court, District of New Jersey, No. 25-03057.

(Reporting by Jonathan Stempel in New York; Editing by Bill Berkrot and Diane Craft)

((jon.stempel@thomsonreuters.com; +1 646 223 6317; Reuters Messaging: jon.stempel.thomsonreuters.com@reuters.net))