Six multiple listing services — Arizona Regional MLS, Bridge MLS, Canopy MLS, REcolorado, Hive MLS and Doorify MLS — have filed a federal lawsuit against Compass International Holdings, asking a judge to protect their cooperation rules from the brokerage's antitrust challenges. The filing lands in the Southern District of New York just two days after a similar lawsuit from a California MLS network, signaling that the legal battle over Compass's private-listing strategy is spreading well beyond one region.
MLSs Seek Court Protection From Antitrust Claims
According to HousingWire, the six MLS plaintiffs filed suit seeking declaratory and injunctive relief, asking the court to let them continue enforcing their existing cooperation rules and to permanently bar Compass from bringing antitrust claims that challenge those policies. The plaintiffs argue that Compass's practice of publicly marketing office-exclusive or private listings before submitting them to the broader MLS system gives the brokerage an unfair competitive advantage and undermines the MLS system itself, the outlet reports.
The dispute traces back to early September, when Compass sent demand letters to MLSs across the country threatening legal action if they didn't stop fining or penalizing Compass agents for publicly marketing office-exclusive listings before posting them more broadly, per the same report. Compass CEO Robert Reffkin said at the time that his firm would spend millions of dollars pursuing litigation against noncompliant MLSs. Unlock MLS and OneKey MLS have publicly rejected Compass's demands, though as of the HousingWire report neither had filed its own lawsuit.
A Parallel Fight Already Underway in California
This isn't the first MLS network to go to court over the issue. California Regional MLS filed a similar lawsuit on Oct. 5 in the same Southern District of New York courthouse, as reported by Inman. That filing asked the court to declare CRMLS Rules 7.9 and 7.9.1 lawful under the Sherman Antitrust Act and California's Cartwright Act — essentially the same defensive posture the six newer plaintiffs are now taking. Compass, for its part, has filed its own lawsuit against CRMLS alleging its rules unlawfully restrict public marketing of properties outside the MLS, HousingWire notes.
The underlying rules at issue stem from industry-wide standards set by the National Association of Realtors, whose Clear Cooperation Policy generally requires a listing broker to submit certain residential listings to the MLS within one business day of publicly marketing them, according to the National Association of Realtors. That public marketing definition is broad, covering everything from yard signs and flyers to brokerage websites and email blasts, while still giving individual MLSs discretion to set delay periods before a property must appear on public search sites like Zillow.
Compass's Broader Legal Entanglements
The MLS lawsuits arrive alongside a separate, bruising fight between Compass and Zillow. A federal court in Illinois recently denied Zillow's request for a preliminary injunction and instead ordered its claims against MRED, the Chicago-area MLS, into private arbitration, per HousingWire's reporting on that ruling. Zillow's claims against Compass itself were paused pending the outcome of that arbitration, and the court's decision was explicitly not a final ruling on Zillow's underlying antitrust and competition allegations.
Compass completed its acquisition of Anywhere Real Estate on Jan. 9, 2026, a deal that reshaped the brokerage landscape, according to a filing with the U.S. Securities and Exchange Commission. That merger has only intensified scrutiny of Compass's market position as it simultaneously pushes MLSs around the country to loosen their public-marketing rules.
With a California network, a half-dozen newly filed plaintiffs, and MLSs in New York already pushing back publicly, the legal fronts in this fight keep multiplying — and each new filing is built around the same core question of whether MLSs can keep requiring brokers to share listings broadly, or whether Compass can carve out its own rules for how homes get marketed to the public.
