Brill Maritime Inc., d/b/a Export Yacht Sales, has filed a lawsuit in the Southern District of Florida against Boats Group LLC. The suit accuses Boats Group of “antitrust violations pursuant to the Sherman Act” and for “unfair methods of competition under the Florida Deceptive and Unfair Trade Practices Act.”

Boats Group is the parent company of Boat Trader, YachtWorld and boats.com. In the past, all three platforms competed against one another.

“These platforms serve as critical advertising and lead-generation tools for boat brokerages, dealers and other sellers throughout the U.S.,” the filing reads. The lawsuit further alleges that Boats Group “has willfully acquired, maintained and expanded monopoly power in this market by engaging in exclusionary and anticompetitive conduct, including the serial acquisitions of its main competitors, unilateral price increases, restrictive contractual terms and practices that hinder entry and expansion by rival platforms.”

Brill Maritime—a Miami-based boat brokerage firm—purchased subscriptions from Boats Group to advertise its marine inventory. The firm alleges being forced to pay “supracompetitive prices for essential marketing services, with effectively zero viable alternatives available.”

“Boats Group’s exclusionary behavior has suppressed competition, harmed sellers and brokerages, and distorted the structure and dynamics of the online boat sales marketplace,” according to the lawsuit.

Brill Maritime is seeking an award of actual damages, treble damages, Brill Maritime’s attorneys’ fees and for the courts to limit or fully discontinue Boats Group’s alleged monopoly.