Zillow has filed a federal antitrust lawsuit against Midwest Real Estate Data (MRED) and Compass, alleging the Chicagoland MLS and the nation’s largest brokerage conspired to withhold listing data and pressure Zillow to carry private “hidden” listings nationwide, according to a company announcement.
The complaint, filed on Tuesday in federal court in Chicago, accuses MRED and Compass of coordinating to threaten Zillow’s access to the Chicagoland listing feed unless the portal agreed to display Compass private listings across the United States. Zillow said this conduct amounts to an unlawful group boycott and abuse of monopoly power under the federal Sherman Antitrust Act.
Zillow alleges that MRED and Compass are colluding to protect and expand private listing networks that keep some homes off public portals and restrict visibility to buyers working with certain brokerages.
Alleged scheme escalated after April 2025
According to the complaint, the alleged scheme escalated after April 2025, when Zillow adopted its Listing Access Standards, which Zillow said were aimed at restricting “hidden” or private listings on its platforms. Zillow contends Compass responded by urging multiple MLSs to cut off Zillow’s data feeds unless it reversed those standards.
In April 2026, MRED and Compass announced a partnership to expand MRED’s private listing network nationwide. The arrangement allowed Compass agents across the country to input listings into MRED’s system. Zillow alleges that the explicit aim was to shield these listings from “pro-transparency” platforms and extend MRED’s leverage beyond its Chicago-area footprint.
By early May 2026, MRED allegedly demanded that Zillow reinstate Compass private listings in markets hundreds of miles outside MRED’s traditional service area. On the same day, Zillow says, the technology provider that distributes MRED’s listing feed threatened to terminate Zillow’s access entirely if it did not comply. MRED CEO Rebecca Jensen chairs that distributor’s board, a dual role Zillow cites as evidence that the threat and its enforcement mechanism were coordinated.
Zillow says the message was clear: Either allow Compass private listings nationally or lose access to all Chicagoland listings. The company’s filing cites public social media comments by a Compass agent and a response from Compass CEO Robert Reffkin as evidence that Compass knew MRED’s control over the local data pipeline could be used as leverage against portals that enforce stricter listing standards.
Alleged effort to go beyond Chicago
The complaint describes a broader effort to align MLS policies across regions. Zillow says a May 11 email from a Compass executive to the CEO of a North Carolina-based MLS urged that organization to “rigorously enforce existing policies that prevent the rise of off-MLS databases” by May 20, which Zillow characterizes as a push to cut off portals that exclude certain private listings. In exchange for complying with the request, Zillow claims Compass offered to keep its listings exclusively within that MLS’s territory.
Compass also announced partnerships with Realtracs, a Tennessee-area listing feed provider and The MLS/CLAW in California over the past few weeks. Those entities adopted rules that bar platforms from excluding listings based on a participant’s identity, broker or agent, mirroring the policy shift at MRED, according to the lawsuit.
The suit alleges MRED agreed to use its control over Chicagoland listing data as “a weapon” against portals that did not carry private listings, in exchange for Compass subsidizing MRED membership costs for up to 100,000 Compass agents nationwide. Zillow says this could triple MRED’s size and expand its ability to impose rules on portals and other industry participants outside its traditional market.
An ongoing spat
Friction between Zillow, MRED and Compass began over a year ago, intensifying after Zillow’s roll out its Listing Access Standards, which Compass filed a since abandoned antitrust lawsuit over. According to the complaint, Reffkin contacted at least eight regional MLSs, arguing that MLSs should “discipline” Zillow for those rules by blocking the portal from IDX and VOW feeds if it did not reverse course.
Zillow alleges that MRED leadership signaled early willingness to act. In October 2025, Jensen allegedly warned Zillow that MRED would cut off its data access if the portal applied its transparency standards in the region and MRED later revised its rules to support that stance.
The complaint also points to broader industry effects. By February 2026, after MRED rewrote its rules but before the formal MRED–Compass nationwide partnership was announced, Zillow says Redfin dropped a similar set of transparency standards just prior to Compass announcing its mutually exclusive deal with Rocket and Redfin to publish its coming soon listings on Redfin.
Zillow is asking the court to block MRED from enforcing its revised rules and from cutting off Zillow’s data access. It is also seeking treble damages and attorneys’ fees.
“The writing is on the wall,“ the complaint states. “If defendants’ unlawful conspiracy is not enjoined, defendants will work to ensure no portal dares to enact similar policies to ensure transparency in real estate.
“Compass and MRED — two competitors in Listing Creation and Distribution — cannot conspire to boycott a competitor’s access to Chicagoland listings. And MRED cannot use its monopoly power over those listings as a cudgel to prevent a competitor from effectively competing in Chicagoland or beyond.”
In an emailed statement a Compass spokesperson said Zillow was “punishing agents for merely following their clients’ lawful instructions on how they want their homes marketed.”
“Compass believes homeowners should have the right to decide how to market their homes. The industry is evolving to give consumers more choice and we support that progress,” the spokesperson added. “We remain committed to advocating for homeowner choice and an open, competitive marketplace.”
MRED did not immediately return HousingWire’s request for comment.
This article was written by Brooklee Han and generated with the assistance of HousingWire Automation. It was reviewed by a HousingWire editor before publication. The system helps convert company announcements and industry data into HousingWire-style news coverage.