Compass has initiated a lawsuit against Zillow, alleging that the real estate marketplace engages in anticompetitive practices by banning private home listings on its platform.

The lawsuit, filed in New York federal court on June 23, 2025, specifically challenges a new Zillow policy that mandates any publicly marketed home listing must be published on Zillow within one day.

Zillow's policy, set to take effect on June 30, aims to block non-compliant listings from its platforms after repeated offenses, ensuring that all listings are accessible to potential buyers.

Compass argues that this policy creates an uneven playing field, favoring large brokers and limiting competition, ultimately designed to maintain Zillow's monopoly in the real estate market.

The lawsuit characterizes Zillow as a dominant platform, citing its acquisitions of competitors and the network effect that positions it as the essential destination for home buyers.

In defense, Zillow claims that its policy promotes transparency and prevents market fragmentation, asserting that it benefits both buyers and sellers by maximizing exposure.

A Zillow spokesperson emphasized that the listing standards are supported by many brokerages and consumer advocates, dismissing Compass's accusations as unfounded.

To bolster its case, Compass has enlisted the expertise of Ken Dintzer, a notable antitrust lawyer, to represent them in this legal battle.

This lawsuit emerges amid a turbulent real estate market characterized by slow home sales and ongoing regulatory changes, with existing home sales experiencing only a slight increase of 0.8% in May 2025.

The housing market is currently facing challenges, including high home prices and mortgage rates exceeding 6%, contributing to the lowest existing home sales since 2009.

As of the report's publication, Zillow has not publicly responded to the lawsuit, leaving the industry to speculate on the potential ramifications.

This legal action is part of a broader trend where Compass is challenging multiple local brokerages and MLSs across the U.S. regarding their policies on private listings.