CoStar Group Inc. Sues Zillow Over Alleged Copyright Infringement

In a significant legal development, CoStar Group Inc., a leading commercial real estate information and analytics provider, has filed a lawsuit against Zillow, accusing the online real estate giant of massive copyright infringement. The lawsuit, filed in New York federal court, alleges that Zillow unlawfully used over 46,000 of CoStar’s watermarked real estate photographs. These images were reportedly displayed more than 250,000 times on Zillow’s platform and extended to partner sites such as Redfin and Realtor.com.

CoStar’s complaint highlights that Zillow’s actions constitute a deliberate choice of infringement over investing in its own content. This legal action follows a prior jury verdict against Zillow for similar image theft, underscoring a pattern of behavior. CoStar estimates that the damages from this infringement could exceed $1 billion, seeking unspecified compensatory and punitive damages.

The lawsuit comes at a time when CoStar’s stock is experiencing slight volatility. As of July 30, 2025, CoStar’s shares were trading at $95.28, down $0.31 or 0.32 percent on the Nasdaq. This legal battle could have significant implications for both companies, given CoStar’s substantial market capitalization of $39.38 billion and its high price-to-earnings ratio of 364.71.

CoStar Group Inc., headquartered in the United States, operates in the real estate sector, providing professional services through its online marketplaces and analytics platforms. The company specializes in commercial real estate research and data, catering particularly to the hotel industry.

Zillow, on the other hand, has not yet responded to requests for comment regarding the lawsuit. The outcome of this legal dispute could potentially reshape the landscape of online real estate platforms, emphasizing the importance of intellectual property rights in the digital age.

This case follows CoStar’s previous legal victory in 2019, where it obtained a $500 million award against Xceligent for the publication of 38,489 copyrighted photographs. The current lawsuit against Zillow underscores CoStar’s commitment to protecting its intellectual property and maintaining the integrity of its content offerings.