CoStar's $470M Trading Volume at Rank 254 as Shares Plunge on Zillow Lawsuit

On August 13, 2025, CoStar Group (CSGP) traded with a volume of $470 million, ranking 254th in daily trading volume. The stock fell 1.02% to $87.56, extending its losing streak to six sessions as investor caution persisted over a legal dispute with Zillow. CoStar alleges Zillow infringed on its copyright by distributing over 46,000 of its real estate images, potentially seeking damages exceeding $1 billion. The lawsuit highlights the company’s ownership of millions of professionally curated property photographs, which it claims were used over 250,000 times on Zillow’s platform. Zillow has not yet commented on the matter, leaving uncertainty about the case’s financial and operational implications for CoStar.

The prolonged decline reflects broader concerns about litigation risks in the real estate technology sector. CoStar’s legal action underscores its strategic emphasis on protecting intellectual property, a core asset for its market-leading real estate data services. However, the lawsuit’s outcome remains uncertain, and any prolonged legal battle could divert resources from growth initiatives. Analysts note that while CoStar’s long-term fundamentals remain intact, short-term volatility is likely until the case progresses or Zillow responds with a counteroffer.

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