A lawsuit alleging a group of hotel operators artificially increased the price of luxury hotel rooms with the help of a shared database has named industry titans Hilton Worldwide Holdings and Hyatt Hotels Corp. among a list of defendants.

Room renters alleged several hotel chains charged higher prices for rooms due to an agreement to share sensitive information about prices, supply and future plans through hotel market research firm STR, Bloomberg Law reports.

The complaint, filed Tuesday in the U.S. District Court for the Western District of Washington, also says the defendants suppressed competition through their arrangement.

“The information exchanges allowed defendant hotel operators to compare their prices and occupancy with their competitors and to raise prices when they were lower than competitors,” the lawsuit says.

STR, a subsidiary of CoStar, didn't respond to a request for comment before publication.

In addition to CoStar, STR, Hilton and Hyatt, defendants include InterContinental Hotels Group, Marriott International and Accor Group, whose luxury brands include Fairmont, Raffles Hotels & Resorts and Sofitel.

The suit was brought by seven residents of California and Illinois, among other states, and seeks damages under federal antitrust law for purported room overcharges, Reuters reported, adding that the claims are bolstered by information from confidential sources that include an STR software engineer.

The claims in the hotel suit parallel a class-action lawsuit against real estate technology company RealPage. The plaintiffs in that case alleged it conspired with major residential property owners to artificially inflate multifamily rents. The RealPage lawsuit centers around the company's revenue management software and a rent-pricing algorithm that the renters alleged impacted pricing strategies.