Zillow vs the Chicago MLS, What the MRED Fight Means

Start with the rule everyone is fighting about

The National Association of Realtors has a Clear Cooperation Policy: within one business day of publicly marketing a property, the listing broker must submit it to the MLS so every member can see it. The idea is simple. If a home is marketed to some buyers, it should be available to all of them.

In March 2025 the trade group kept that policy and added a narrow exemption that lets a seller delay public syndication for a window, with a signed disclosure. It was a compromise that did not fully satisfy either side.

Zillow drew a line

In April 2025, Zillow announced listing access standards, enforced starting June 30, 2025. If a listing was publicly marketed off the MLS for more than a business day, Zillow would not show it. Zillow framed it plainly: if a listing is marketed to some buyers, it should be marketed to all buyers. Repeat violations could keep a listing off Zillow for the life of the listing contract. Redfin adopted a parallel rule, while a few competitors took the opposite side.

Compass sued, and lost

Compass, which had pushed to scrap Clear Cooperation, sued Zillow in federal court in New York in June 2025, alleging an illegal boycott and monopolization. It did not go Compass's way. In February 2026 the judge denied Compass's request to freeze the ban, finding it had not shown a likely antitrust violation, and in March 2026 Compass voluntarily dropped the suit. Zillow's standards survived federal scrutiny.

Then it came to Chicago

This is where it gets local. MRED, Midwest Real Estate Data, is the Chicago-area MLS, and it has run a private listing network since 2016. In May 2026, Zillow sued MRED and Compass in federal court in Chicago, alleging they coordinated to force Zillow to display private listings. MRED responded by cutting its data feed to Zillow on May 20, 2026, and Chicago-area Zillow inventory reportedly fell from roughly 5,000 listings to about 700 within hours.

Two days later, a federal judge granted a partial temporary restraining order. Zillow's feed was restored, but Zillow was barred from banning listings in the ZIP codes where MRED had carried listings over the prior year. As of June 2026 the case is ongoing and unsettled, with motions still pending, so treat any outcome as not yet decided.

Our opinion: the leverage is the data

Here is the lesson, and it is opinion grounded in the record above. Everyone assumed the portals held the power, because they hold the buyers' attention. Chicago showed the reverse can be true. An MLS that controls the listing data can make a national portal's local inventory collapse overnight, then force it into court to get the feed back. Control of the data, not the wording of a policy, is where the real power sits.

We will not overstate the numbers that are still single-sourced, and we will not pretend the litigation is over. What is clear is that the private-versus-public listings fight did not get settled at the top. It fragmented down to portals and individual MLSs setting their own terms.

What it means for Chicago sellers and buyers

For sellers, the evidence still favors broad exposure. Private or delayed marketing is a limited tool with a real tradeoff, and outside MRED's protected ZIP codes a privately marketed home can be suppressed on the biggest portals. For buyers, watch for a two-tier market where some inventory is visible only to certain clients or networks. For everyone, this is unsettled, so get current advice before you rely on any one portal as the full picture of what is for sale.