Complaint Alleges Anticompetitive Practices Harmed Commercial Real Estate Brokers Nationwide
NEW YORK — DiCello Levitt LLP, along with co‑counsel Webster Book LLP and Sperling Kenny Nachwalter, LLC, has filed the first antitrust class action challenging CoStar Group, Inc. and CoStar Realty Information, Inc.’s alleged monopolization of the commercial real estate (“CRE”) online listing and information services markets.
Filed in the U.S. District Court for the Eastern District of Virginia, the lawsuit is brought on behalf of commercial real estate brokers and other market participants who paid supracompetitive fees for CoStar’s listing and data products. The complaint alleges that CoStar—the dominant provider of CRE listing and information platforms, including LoopNet and CoStar—unlawfully restrained customers’ ability to work with CoStar competitors and maintained monopoly power in violation of Sections 1 and 2 of the Sherman Act.
“We filed this case because commercial real estate brokers and firms are being squeezed by a system that leaves them with no real choice,” said Partner Greg Asciolla, Chair of DiCello Levitt’s Antitrust and Competition Litigation Practice. “We believe CoStar used its dominant position to lock up customer data, shut out competition, and raise prices. This is the first class action to challenge that conduct and restore fairness and choice to the commercial real estate industry.”
According to the complaint, CoStar controls roughly 80% of the national markets for internet‑based commercial real estate listing and information services and used a multi‑pronged scheme to entrench that dominance. The suit alleges CoStar imposed non‑negotiable restrictions preventing customers from sharing their own listings and data with CoStar competitors, coerced major brokerages into long‑term non‑competition agreements, and enforced those restraints through digital watermarks, IP blocks, threats, and scraping competitor websites—leaving customers with little choice but to pay inflated prices.
The complaint further alleges that CoStar’s conduct has raised barriers to entry, foreclosed competition from emerging and innovative platforms, and harmed thousands of brokers and firms nationwide who rely on CRE data and listing services to conduct their businesses. Plaintiffs seek damages on behalf of a nationwide class, as well as injunctive relief to restore competition to the commercial real estate data and listings markets.
The case is Shapiro Hospitalities LLC d/b/a Grand & Co. v. CoStar Group, Inc., et al., Case No. 1:26‑cv‑01027, filed in the United States District Court for the Eastern District of Virginia. A copy of the complaint is available here.
The DiCello Levitt team on the matter is led by Steven Groopman and includes Greg Asciolla, Jonathan Crevier, Geralyn Trujillo, and Corey Lipton.
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Media Contact
Caitlin Whitehurst, Director of Communications, cwhitehurst@dicellolevitt.com
