Compass Sues Zillow for Alleged Abuse of Monopoly

Compass is suing Zillow for enacting a listings ban for agents who do not upload new real estate listings to a Multiple Listing Service (MLS).

Zillow's listings standards policy, announced in April, outlines that realtors will be warned and subsequently banned from publishing listings on Zillow for not uploading listings to the MLS in a timely manner.

But brokerage Compass is asking federal judges to block Zillow from enacting its ban, citing anticompetitive behaviour, namely its gatekeeping of home listings and for breaking antitrust laws.

In Compass' words:

To protect its market dominance, Zillow has retaliated against competitive threats by enacting an exclusionary policy.

Zillow uses [its] ban to block real estate search rivals like Compass from competing head-to-head.

Commenting on his personal LinkedIn page, Compass CEO Robert Reffkin said:

"Some things just need to be settled in court. But I am shocked that there aren’t more leaders in the industry standing up to Zillow."

"Compass is suing Zillow for abusing its monopoly power to ban homeowners and their agents for marketing homes off Zillow’s website."

"Imagine if Amazon banned every seller that offered a product on their own website first. That’s what Zillow is doing in real estate. Only a monopoly would think they can get away with banning anyone."

An accompanying image on Reffkin's post shows a lawsuit submitted to the United States District Court for the Southern District of New York, naming Compass as the plaintiff and Zillow as the defendant. The lawsuit was filed on the morning of June 23, 2025.

In a statement, Zillow called the claims "unfounded" and said that it would vigorously defend itself and reiterated its stance on private listings.

"When a listing is publicly marketed, it should be accessible to all buyers - across all platforms," Zillow said.

"Hiding listings creates a fragmented market, limits consumer choice and creates barriers to homeownership, which is bad for buyers, sellers, and the industry at large, especially in this inventory and affordability-constrained environment,"

This lawsuit raises a key question. As Debra Kamin put it in the New York Times, "Who controls home listings?"

On one hand, Compass is the United States' most successful brokerage by sales volume. On the other hand, Zillow is undoubtedly the country's leading real estate shop window.

Zillow uses real estate listings on its site to sell leads to agents who pay the company a fee for access to this service. The more listings Zillow has access to via the MLS, the higher its revenue ceiling. Meanwhile, Zillow promotes total transparency in the market, a sentiment shared by Redfin, named as a co-conspirator but not a defendant in the lawsuit.

On the other side of the market, brokerages like Compass want access to exclusive (or 'pocket') listings as a core differentiator.

If every listing in the country is automatically uploaded to Zillow's home search platform, Compass becomes less useful and less lucrative to agents, particularly those paying for Compass' Private Exclusives package—a strategic focus for the brokerage in recent months.

Private Exclusives are only accessible to Compass agents, but that product doesn't work if Zillow succeeds in having all listings publicly visible, all the time.

Zillow's approach has historically followed rules set out by the National Association of Realtors (NAR) in 2019, but these were amended earlier this year for a softer approach.

The Clear Cooperation Policy (CCP), for all its faults and controversies, has acted as a benchmark for best practices in the United States for several years, and Zillow has benefited hugely from the stringent adherence by agents. At its core, CCP helped build a library of a highly transparent, nationwide real estate market. It's great for consumers who want to see as many properties as possible when they search for a new home, and it's great for Zillow's business model.

But plenty of brokerages and agents are working hard for listings. And many also want to provide off-market and pre-market opportunities for the sellers they represent, but have been unable to shake off CCP and Zillow. It's part of the reason why CoStar's Homes.com attracts agents via the "your listing, your lead" tagline and it's why brokerages like Compass are so keen to find any way possible to make their listings stand out.

Zillow's ban may discourage agents from using brokerages like Compass due to the threat of not being able to upload any future listings to Zillow in the future.

This legal showdown brings together two of the biggest players in the country. While there have been plenty of back-and-forth lawsuits between major real estate companies in recent years, the outcome of this lawsuit represents a potentially industry-shifting judgment that could have significant outcomes.