CoStar’s $260M Volume Plunges to 378th Amid Zillow Copyright Battle as Shares Climb 0.47%

CoStar Group (CSGP) rose 0.47% on August 14, 2025, with a trading volume of $260 million, a 45.29% decline from the previous day, ranking 378th in market activity. The stock’s performance was influenced by a high-profile copyright infringement lawsuit against Zillow, filed by Homes.com’s parent company. The suit alleges Zillow systematically violated CoStar’s intellectual property rights, potentially exposing Zillow to over $1 billion in damages. This legal action, alongside CoStar’s recent earnings beat, has drawn investor attention to the company’s market positioning.

CoStar’s second-quarter results highlighted a strategic focus on recurring revenue streams and operational efficiency, with upgraded 2025 guidance reflecting strong net bookings growth. Analysts noted robust demand for its real estate data services, including multifamily rent growth and home price appreciation reports. However, the prolonged legal dispute with Zillow introduces uncertainty, as the outcome could impact CoStar’s reputation or market share in the digital real estate sector. The lawsuit, now in its 15th day of public reporting, remains a key risk factor for near-term volatility.

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