Selling products on Amazon is already an expensive gamble. Now, federal regulators and state officials say the house was quietly cheating the game.
The Federal Trade Commission, alongside 22 state attorneys general, filed a major antitrust and consumer protection lawsuit against Amazon. The core allegation is straightforward: Amazon secretly manipulated its digital advertising auctions. This scheme reportedly overcharged roughly 1.2 million brands and third-party sellers by an estimated $20 billion or more since 2019.
If you run a small business relying on Sponsored Products, Sponsored Brands, or Sponsored Display ads to stay visible, this legal battle exposes how your advertising budgets were quietly squeezed behind closed doors.
How the Advertising Auction Was Supposed to Work
For years, Amazon pitched its ad placement system as a standard generalized second-price auction. Under this widely accepted industry model, an advertiser sets a maximum bid for a keyword or product placement. If they win the auction, they don't actually pay their maximum bid. Instead, they pay just enough to beat the runner-up—traditionally described as one cent more than the second-highest bid.
Sellers trusted this system because it protected them from overpaying. It created a predictable environment where bidding strategies could be mapped out based on clear rules.
Except the rules changed without warning.
The Hidden Soft Reserve Price
According to the FTC complaint, Amazon introduced an undisclosed mechanism in 2019 known internally as a "soft reserve price". This hidden surcharge altered the math entirely. Instead of paying one cent over the second-place bidder, winners were forced to pay much closer to their maximum bids—or the full amount of their bid altogether.
The lawsuit highlights internal company notes and emails showing that senior executives and economists understood exactly what they were doing. One 2024 discussion explicitly acknowledged that the setup was a clever, non-transparent way to drive revenue. Another internal document warned that revealing the surcharges would cause irrevocable damage to advertiser trust and trigger a downward spiral of lower bids.
To prevent that panic, Amazon allegedly kept the fees concealed. When curious advertisers asked direct questions about shifting auction costs, company representatives offered misleading answers.
The numbers detailed in the complaint are staggering. For standard Sponsored Products ads, the frequency with which an advertiser paid their exact maximum bid skyrocketed from roughly 30 to 40 percent in 2021 to an astonishing 80 percent by 2024.
Who Actually Pays for the Surcharges
When operating margins shrink for third-party merchants, the financial pressure doesn't just disappear. Brands dealing with inflated ad acquisition costs have to make up the difference somewhere.
That means higher prices on everyday essentials like groceries, health items, clothing, and electronics. When Amazon extracts billions in extra ad revenue from sellers, consumers ultimately foot the bill through inflated retail prices across the marketplace.
Amazon Defense and Next Legal Steps
Amazon has pushed back hard against the allegations, calling the lawsuit misguided and built on a fundamental misunderstanding of how digital advertising works. The company argues that average cost-per-click rates remained flat from 2019 through 2024 when adjusted for inflation, and claims that winning bids actually dropped significantly over a similar timeframe. Furthermore, Amazon insists its systems prioritize ad relevance over raw bid prices, saving sellers billions.
The federal court in Washington state will ultimately decide which version of events holds up under scrutiny. The plaintiffs are seeking severe financial penalties, restitution for affected businesses, and a permanent injunction to halt the alleged practices.
If you manage ad spend on the platform, audit your historical campaign performance metrics closely and keep a tight grip on your maximum bid thresholds while this litigation unfolds.
