By Mike Scarcella

April 2 (Reuters) - A lawsuit filed in Chicago federal court claims that construction equipment giant United Rentals URI.N and four rivals conspired with a data services platform to fix prices, causing thousands of businesses to overpay for excavators, cranes and other vehicles.

Illinois-based small business Zags Roofing filed the proposed class action on Tuesday, accusing United Rentals, Sunbelt Rentals and others of forming an illegal price-fixing cartel.

The lawsuit alleged the equipment rental companies violated antitrust law by collectively sharing competitive, nonpublic inventory and pricing data with analytics company Rouse Services, which provides revenue management software used to set rate benchmarks in the industry.

United Rentals and the other defendants were able to raise prices without fear of being undercut, according to the lawsuit, filed by plaintiffs’ firms Berger Montague; Hausfeld and Edelson.

The victims are “those companies shouldered with the responsibility of building our nation’s housing, commercial centers, and infrastructure,” said Hausfeld’s Gary Smith Jr in a statement.

United Rentals, Sunbelt Rentals, Rouse Services and its parent RB Global, which is also a defendant, did not immediately respond to requests for comment.

Stamford, Connecticut-based United Rentals, the country’s largest construction rental equipment provider, reported $15 billion in total revenue last year.

The lawsuit said demand for construction rental equipment was “significant and continuous.” Renting equipment is more affordable, especially for smaller companies that might need a dozer or lift only for a short amount of time, according to the lawsuit.

The plaintiffs' lawyers estimated potentially hundreds of thousands of members of the proposed class.

The rental market has become increasingly concentrated over 20 years based on hundreds of acquisitions by the leading companies, according to the lawsuit.

Before Rouse’s data services came to dominate the industry, the lawsuit said, rental companies independently set rental pricing based on their own cost and demand factors.

Revenue management platforms have come into focus in other lawsuits targeting hotels and rental markets such as multifamily residential housing.

The construction equipment lawsuit is seeking unspecified monetary damages under antitrust law, and a court order to break up the alleged price-fixing conspiracy.

The case is AXG Roofing LLC v. RB Global Inc et al, U.S. District Court for the Northern District of Illinois, No. 1:25-cv-03487.

For plaintiffs: Eric Cramer and Michaela Wallin of Berger Montague; Gary Smith and Swathi Bojedla of Hausfeld; and Natasha Fernández-Silber and Abby Lemert of Edelson

For defendants: No appearances yet

(Reporting by Mike Scarcella)