Zillow, Compass, MRED Argue MLS Listing Control in Court

A federal judge in Chicago is presiding over an antitrust case involving Zillow, Compass, and Midwest Real Estate Data (MRED), focusing on who controls the visibility of real estate listings. The parties submitted post-hearing briefs in the first half of July, revealing significant disagreements.

In a 48-page filing, Zillow accused MRED and Compass of acting in unison to obstruct its Listing Access Standards. Zillow alleged that Compass used MRED to circulate private exclusive listings, thereby triggering a rule violation and justifying the termination of Zillow's data feed. Zillow cited an email from October 2025, where Compass CEO Robert Reffkin urged multiple Multiple Listing Services (MLSs) to "discipline" Zillow by revoking its feed access if the standards were not "immediately repealed." Zillow's Listing Access Standards, introduced in April 2025, stipulate that a home will be removed from Zillow if it is not available on IDX or VOW feeds within one business day of public marketing. This rule directly impacts private exclusive listings sold by Compass before they are officially listed on the MLS.

MRED and Compass presented a contrasting narrative in their joint 40-page brief, asserting that any alleged harm was "self-inflicted." They argued that if Zillow desires access to MRED's data feed, which they claim Zillow receives at virtually no cost, Zillow simply needs to refrain from subjectively banning listings. Their brief further contended that Zillow's transparency argument is flawed, stating that Zillow's ban policy actually promotes secrecy by pushing sellers towards private listings rather than the open MLS. MRED maintains that its display rules adhere to objective criteria, stemming from a 2008 settlement between the Department of Justice and the National Association of Realtors, which prohibited the MLS from imposing certain restrictions.

The core of the dispute lies in Zillow's Listing Access Standards, which aim to ensure timely data sharing for listings. Compass, a real estate brokerage firm, sells private exclusive listings before they enter the broader MLS, a practice that Zillow's standards would affect. MRED, a major MLS serving the Chicago metropolitan area, is caught in the middle, with Zillow alleging it facilitated Compass's actions. The outcome of this case could significantly influence how real estate listing data is accessed and controlled across the industry, impacting brokerages, MLSs, and online real estate portals.