Amazon is facing a major regulatory challenge after the Federal Trade Commission and 22 states accused the e-commerce giant of secretly increasing advertising costs for businesses using its platform. The lawsuit alleges that Amazon altered the mechanics of its advertising auctions over several years, potentially generating tens of billions of dollars in additional revenue while affecting more than one million brands and sellers. The case puts renewed attention on the economics and transparency of digital advertising marketplaces.

FTC Targets Amazon’s Advertising Auction Practices

The lawsuit focuses on Amazon’s Sponsored Products, Sponsored Brands and Display advertising. According to the FTC, Amazon represented its advertising system to more than 500,000 small and medium-sized businesses as a second-price auction, meaning the winning advertiser would generally pay slightly more than the next-highest competing bid rather than its entire submitted bid.

The regulator alleges that Amazon began making changes in 2019 by introducing an undisclosed mechanism internally described as a “soft reserve price.” The complaint further alleges that Amazon used an “invented auction participant” to increase the price advertisers had to pay. The FTC argues that this practice effectively allowed Amazon to manufacture additional competitive pressure within its own auction system.

Advertising Revenue Raises the Stakes

The allegations are particularly significant given the scale of Amazon’s advertising business. The company generated more than $68 billion in advertising revenue last year, demonstrating how strategically important the segment has become beyond Amazon’s traditional retail operations.

The FTC claims the alleged changes resulted in Sponsored Products advertisers paying their full winning bids close to 80% of the time. If established in court, that would represent a substantial departure from advertisers’ understanding of how the auction mechanism operated and could raise broader questions about pricing transparency in digital advertising.

For sellers and brands, advertising costs directly influence product visibility, customer acquisition expenses and ultimately profitability. Any structural increase in advertising prices can therefore affect not only Amazon’s revenue but also the economics of thousands of businesses competing for consumer attention.

Amazon Rejects the FTC’s Allegations

Amazon has characterized the lawsuit as misguided and disputed the regulator’s interpretation of its advertising system. The company argues that its auctions process billions of bids across different advertising placements and formats, meaning pricing can naturally vary depending on the circumstances. Amazon also maintains that advertisers are properly informed about its pricing mechanisms.

The disagreement creates a significant legal and strategic issue for Amazon. The company must defend its auction practices while protecting an advertising operation that has become an increasingly important source of revenue. For investors, the case introduces uncertainty around potential financial remedies, operational changes and future regulatory scrutiny of Amazon’s marketplace.

What the Case Could Mean for Digital Advertising

The lawsuit could have implications extending beyond Amazon if regulators succeed in establishing that undisclosed auction mechanics constitute an unfair business practice. Digital advertising platforms rely heavily on complex automated bidding systems, making transparency and advertiser understanding increasingly important as companies allocate larger portions of their marketing budgets to online marketplaces.

The next phase of the case will be closely watched by advertisers, sellers and investors. The central question will be whether Amazon’s auction practices represented legitimate pricing mechanisms or improperly increased costs through undisclosed changes. A stronger regulatory response could ultimately reshape how major digital platforms structure and disclose advertising auctions.