Federal regulators, joined by 22 U.S. states, sue Amazon over allegations that it overcharged advertisers for online ads through a “secret” surcharge or manipulation of advertising pricing. The FTC says Amazon overcharged advertisers by tens of billions of dollars over multiple years, with the higher costs largely passed along to consumers, according to outlets covering the complaint.

The lawsuit also alleges that Amazon altered advertising auction dynamics to benefit higher bids, effectively steering outcomes and inflating ad prices. Outlets report that the dispute centers on how advertisers bid and how pricing results are determined on Amazon’s website and app.

Amazon denies the allegations across reports, saying the regulators misunderstand how its advertising market works. The company argues it does not deceive advertisers, and it disputes claims that the practices harm consumers, pointing instead to potential savings and improved performance for advertisers. Bloomberg and others frame the case as another clash between Amazon and the FTC, while multiple outlets emphasize the scale of the alleged overcharges and the regulators’ claim of ongoing conduct.