RealPage, which makes property management software, was sued Friday by the U.S. Justice Department and eight attorneys general for allegedly helping apartment and building managers around the country collude to drive up unit prices.

The Richardson, Texas-based outfit is accused of contracting with rival landlords to absorb info about their rates and lease terms to train RealPage’s recommendation algorithms, and in the process discouraging competition among property owners who defer to the company’s recommendations on pricing and other terms.

It’s the DOJ’s first big algorithmic collusion case and comes as rent in the U.S. skyrockets, climbing 33% since March 2020, according to Zillow.

RealPage, which was acquired by private equity firm Thoma Bravo in 2021 for $10.2 billion, commands 80% of the market for commercial revenue management software for conventional multi-family housing rentals in the U.S., according to the lawsuit. The company denies any wrongdoing.