The U.S. Federal Trade Commission (FTC) has filed a new lawsuit against Amazon in conjunction with 22 states, accusing it of charging additional fees to merchants through secret mechanisms over a period of seven years. Specifically, Amazon changed the originally promised “sub-luxury auction” mechanism to actually collect the full bid amount, and used hidden surcharges called “soft reserve prices” and fake bidders to inflate prices. The lawsuit claims that this practice affected more than 1 million brand sellers and could potentially bring Amazon billions in additional revenue. In response to the accusations, Amazon argued that the lawsuit misunderstands its bidding mechanism, claiming that it has fully informed merchants about its pricing system and that advertising revenue involves natural fluctuations.