OneKey MLS has joined a federal lawsuit against Compass International Holdings, expanding a legal dispute over how homes for sale are marketed and who can access listing information.
The New York-based multiple listing service became a co-plaintiff alongside California Regional MLS, which originally filed the case. In an amended complaint, the two organizations ask a federal judge to affirm that rules requiring the shared, public marketing of listings are consistent with antitrust law and support an open real-estate marketplace.
A dispute over cooperation rules
OneKey's decision follows its public rejection of demands from Compass to roll back local cooperation policies. The MLS said the case raises questions about the distribution of listing data as more property marketing takes place through private networks and channels outside traditional multiple listing services.
“This case raises questions that extend far beyond any one company or market. It goes to the core of how homes for sale are shared, how everyday buyers access that information, and how we protect a fair, equal housing market for everyone. We believe these issues demand clarity from the court and joining CRMLS gives OneKey a direct, active voice in securing it.”
Richard Haggerty, CEO of OneKey MLS, made the statement in the announcement of the organization's participation in the case. OneKey serves more than 48,000 real-estate professionals across Long Island, New York City and the Hudson Valley.
CRMLS, described as the nation's largest multiple listing service by subscriber count, has been seeking court guidance on whether its listing-cooperation rules can remain in place without conflicting with current antitrust enforcement trends. Art Carter, CEO of CRMLS, said the organization would work with OneKey to defend an open marketplace.
“I’m looking forward to working alongside OneKey MLS in the fight to protect the open marketplace and keep real estate fair and transparent for brokers, agents and consumers alike,”
Carter's statement was included in the announcement. The case places industry rules governing listing visibility at the center of a broader disagreement between traditional cooperative marketplaces and more limited, proprietary distribution systems.
What OneKey alleges
In the amended filing, OneKey argues that keeping listings out of the open MLS can restrict buyers' access to homes, undermine fair-housing objectives and potentially reduce a seller's financial outcome. The organization also contends that Compass participates in cooperative marketplaces to obtain access to listings from other brokers while retaining some of its own inventory in more fragmented systems.
OneKey described that position as “having it both ways” in its filing. The MLS said seller choice and an open, competitive marketplace can coexist, while arguing that clearer judicial guidance is needed over how those principles apply to listing cooperation and off-MLS marketing.
- OneKey MLS: a new co-plaintiff serving more than 48,000 real-estate professionals in the New York region.
- CRMLS: the original plaintiff, described as the largest MLS in the nation by subscriber count.
- Compass: the defendant in the federal dispute over cooperation rules and listing distribution.
The amended complaint does not resolve the legal questions raised by the parties. The court will determine whether the challenged listing practices and cooperation requirements comply with antitrust law. Until then, the case remains a dispute over the structure of real-estate information sharing, rather than a final ruling on the legality of either side's position.
