Median rent in Phoenix is $1,650. If you rent an apartment in a large multifamily building in Arizona, that number was probably set by a piece of software you’ve never heard of.
The software is called YieldStar, and its successor product AIRM (AI Revenue Management). It is made by RealPage, a company headquartered in Richardson, Texas. According to ProPublica’s 2022 investigation, YieldStar at that time covered around 16 million large multifamily units in the United States, a sizable majority of the large-building rental market. RealPage’s own marketing today claims the company serves over 24 million units worldwide. Property managers feed it data on their own units, market demand, and vacancy rates. It spits back a daily rent recommendation for every unit they manage. ProPublica reported acceptance rates from landlords running around 80 to 90 percent.
Arizona Attorney General Kris Mayes filed a state-level suit against RealPage and eleven apartment companies operating in Arizona on February 28, 2024. The federal Department of Justice filed its own case in August 2024 in the Middle District of North Carolina, joined as co-plaintiffs by ten states (California, Colorado, Connecticut, Illinois, Massachusetts, Minnesota, North Carolina, Oregon, Tennessee, and Washington). Arizona was not one of them. RealPage and the DOJ reached a proposed consent decree settlement on November 24, 2025, pending final approval from the federal judge in North Carolina. The ten plaintiff states were not part of that settlement. Class-action suits are also still working through the courts. The fight is still live.
How it actually works
The pitch RealPage makes to landlords is straightforward. Instead of setting rent based on instinct and a spreadsheet, subscribe to a platform that models optimal pricing at the unit level, every day, using data from across the market. The company claims up to seven percent revenue outperformance.
The mechanic that makes this legally contested is the input data. YieldStar didn’t just use a landlord’s own pricing history. It ingested nonpublic, competitively sensitive data from other landlords on the platform. A former RealPage executive told ProPublica that staff pushback on the recommendations was typically ten to twenty percent, meaning roughly 80 to 90 percent of recommendations got accepted. The model was also configured to recommend holding units vacant longer rather than discounting rent. In a conventional market, a landlord sitting on empty units loses money fast. In a market where most of the competing landlords are running the same algorithm, nobody breaks first.
Why this is a policy fight, not a court case
The DOJ case got a settlement, not a conviction. The Duane Morris analysis of the settlement made the point plainly. DOJ is not treating algorithmic pricing as inherently illegal. The settlement forces RealPage to stop ingesting competitors’ nonpublic data and to retrain its models on compliant datasets within 180 days. It does not say shared third-party pricing algorithms are against the law.
That is because antitrust law, specifically the Sherman Act, requires an agreement between competitors. Two landlords who happen to reach the same price by subscribing to the same software have not agreed to anything. They have independently chosen to follow recommendations from a shared vendor. That is parallel conduct, which is generally legal. The law was written when price collusion required a phone call.
This is the loophole. The reason the DOJ went after RealPage at all is that the specific data flows inside the platform (using nonpublic competitor data to train the model, running back-channel consulting calls where executives discussed market positioning) started to look more like coordination than like parallel conduct. The settlement forces that specific behavior to stop. The broader practice of building rent pricing on a shared algorithm is still on the table.
What states are doing while Congress watches
California was first. Assembly Bill 325 was signed by Governor Newsom on October 6, 2025, amending the Cartwright Act to restrict algorithmic rental pricing. New York followed ten days later. Governor Hochul signed Senate Bill 7882, which took effect December 15, 2025. Colorado passed HB25-1004 through both chambers along party lines. Governor Jared Polis vetoed it on May 29, 2025, writing that he had “grave concerns about prohibiting companies using algorithmic pricing software derived from multiple data sources from doing business in Colorado.”
City ordinances have moved faster than state legislatures. San Francisco, Berkeley, Philadelphia, Minneapolis, San Diego, Jersey City, and Seattle have all passed local bans. Bellingham, Washington is putting one on the November ballot.
Arizona has not passed a state ban. The attorney general has sued. The legislature has not moved. The Commerce Committee and the House Science and Technology Committee both have jurisdiction that touches this. Housing affordability is regularly named as a top-three issue by legislators from both parties in Phoenix metro and rural districts. The bill has not been written.
What this means
For everyday renters. If you rent in a large apartment building anywhere in Phoenix, Tucson, Flagstaff, or the Valley suburbs, there is a real chance a daily algorithmic price recommendation is shaping your rent. Your landlord is not sitting in a smoky room colluding with the competition. They are running software that produces a similar coordination effect without the phone call. The DOJ settlement reins in the most legally exposed version of that software. It does not reshape the practice.
For policy people. The antitrust framework inherited from the twentieth century does not catch algorithmic signaling. Two landlords using the same pricing platform produce a market outcome that looks identical to price-fixing without satisfying the Sherman Act’s agreement requirement. Closing that gap requires statutory fixes at the state or federal level, not more litigation. California and New York have done it. Twenty-three other states could move next session if advocates knew which committee chairs to call.
For Arizona legislators. You have the attorney general’s suit, two years of federal discovery, a settlement on the table, a market where 73 percent of units run on this software, and housing affordability ranked as a top issue by nearly every member. The bill is already written in California and New York. Copying it is the easiest policy work your committee will do this session. The question is who picks up the pen.
For enterprises and landlords. If you run a multifamily portfolio using RealPage, you have 180 days from the North Carolina judge’s approval to adapt. Your revenue management software will be running on different inputs by next summer. Expect rent growth recommendations to normalize toward fundamentals. This is not the end of revenue management as a category. It is the end of the phase where the algorithm was doing antitrust work the law was not equipped to name.
Laterstack has reached out to RealPage for comment and will update this story if the company responds.