When climate-risk data disappears

A QUIET DECISION by the nation’s largest homelisting authority may soon determine who's legally responsible for warning homebuyers about climate risk.

- DAVE JONES GUEST CONTRIBUTOR

Last month, the California Regional Multiple Listing Service — the dominant database used by real estate agents in the country’s largest housing market — pressured Zillow to remove climate-risk scores produced by First Street, an independent research group whose flood and wildfire models are widely used by insurers, banks and public agencies. Zillow depends on CRMLS’ feed for individual home and rental listings, so it quickly complied. Overnight, climate-risk information disappeared not only from Zillow's California listings but from every home listed across its national platform.

CRMLS framed this as a dispute about scientific accuracy. But the more significant impact falls on real estate agents.

Under longstanding principles of real estate law and material fact disclosure, agents have a duty to disclose known risks that could materially affect a buyer's decision. When an agent or broker is aware—or reasonably should be aware — of credible hazard data for a property, the information can’t be ignored simply because it vanishes from a consumer-facing site.

By disputing these independent risk models and urging widely used real estate platforms to suppress them, CRMLS has effectively failed to shield agents and brokers from responsibility. Instead, it may actually have done the opposite — making the agents who rely on it legally responsible for disclosures without the support of standardized, third-party transparency tools.