CoStar Group Legal Cases and Litigation

CoStar Group is actively defending its intellectual property and competitive position through multiple high‑profile legal actions, including copyright infringement cases against Zillow and CREXi, and the successful defense against a withdrawn lawsuit by Move Inc., operator of Realtor.com. These matters underscore CoStar Group’s commitment to protecting its original content, investments, and marketplace integrity.

Zillow Litigation

On July 30, 2025, CoStar Group filed a copyright infringement lawsuit against Zillow in federal court in New York for infringing almost 47,000 copyrighted CoStar Group photographs. This is one of the largest image infringement lawsuits in history, and could expose Zillow to more than $1 billion in damages. CoStar Group’s Complaint shows CoStar Group’s watermarked images on Zillow as well as Redfin and Realtor.com, following recent “syndication” deals in which Zillow paid Redfin and Realtor.com to carry Zillow’s listings.
CoStar Group’s Complaint highlights Zillow’s own description of how much information it can obtain from a photograph, recognizing details as granular as granite countertops. Based on Zillow’s own description, identifying and removing CoStar Group-watermarked photos should be straightforward—Zillow just chooses not to do it.

CREXi Litigation

CoStar Group filed a copyright infringement complaint against Commercial Real Estate Exchange Inc. (“CREXi”) in September 2020 in Los Angeles. CREXi, backed by several large venture capital companies, is reportedly one of the biggest real estate data platforms in the country, valued at a half billion dollars ($500 million) in 2022. On June 25, 2025, the Court overseeing the case issued a ruling confirming that CREXi routinely accessed CoStar Group’s LoopNet site, copied listings from there, and took steps to cover up its wrongdoing by screenshotting CoStar Group-copyrighted photographs and cropping out CoStar Group’s watermark. The Court also found that CoStar Group owns all of the tens of thousands of photographs that CREXi deliberately infringed. They were taken by CoStar Group photographers, and registered with the Copyright Office. A trial to determine the damages that CREXi must pay will follow.

Move, Inc. Litigation

Move Inc. operates Realtor.com, an online marketplace that has fallen behind CoStar Group’s Homes.com. Move resorted to filing a lawsuit falsely accusing CoStar Group of using Move trade secrets to build a rival news division. In 2024, Move’s request for a preliminary injunction was denied by a federal judge. In 2025, after multiple other setbacks, Move withdrew its entire lawsuit. CoStar Group paid nothing, and agreed to nothing. Move simply capitulated.