The District of Columbia’s attorney general filed an antitrust lawsuit Tuesday against Amazon alleging that the e-commerce titan is artificially inflating prices across the internet through its demands on third-party sellers.

Attorney General Karl Racine’s lawsuit targets “most favored nation” clauses in Amazon’s agreements with sellers, which state that companies cannot sell their items at lower prices elsewhere online, including their own websites.

The lawsuit, filed Tuesday in D.C. Superior Court, argues that Amazon charges high fees to third-party sellers and that the agreements force those companies and competing online retailers to charge customers higher prices. The lawsuit says the fees charged by Amazon can amount to up to 40% the total sale price. The attorney general called the fees “unreasonably high” and said Amazon can get away with charging them because of its immense market power.

“Amazon has used its dominant position in the online retail market to win at all costs,” Racine said in a statement. “It maximizes its profits at the expense of third-party sellers and consumers, while harming competition, stifling innovation, and illegally tilting the playing field in its favor.

“We filed this antitrust lawsuit to put an end to Amazon’s illegal control of prices across the online retail market. We need a fair online marketplace that expands options available to District residents and promotes competition, innovation, and choice.”  

Amazon did not immediately respond to an email from Spectrum News seeking comment on the suit.

The District of Columbia is seeking the court to order Amazon to end its “anticompetitive practices,” to pay restitution and damages to customers, and to impose fines to deter “future misconduct.”