The European Union has launched a formal antitrust investigation into Amazon, targeting the company’s treatment of third-party sellers on its marketplace platform. The probe centers on whether Amazon uses its dual role – both as a marketplace host and a competing retailer – to gain unfair advantages over the independent businesses that depend on it to reach customers.
What the EU Is Investigating
At the core of the investigation is a concern that has circled Amazon for years: the company collects vast amounts of data from third-party sellers operating on its platform, then potentially uses that data to inform its own private-label product decisions and pricing strategies. For a seller building a niche product category, that kind of exposure to a better-funded competitor who also controls the storefront is not a level playing field.
Regulators are also examining Amazon’s “Buy Box” algorithm – the white box on product pages that defaults customers toward a specific purchase option. Winning the Buy Box is effectively the difference between visibility and invisibility for most sellers. The concern is that Amazon may weight Buy Box placement in ways that favor its own products or sellers who use Amazon’s fulfillment and advertising services, which generates additional revenue for the company regardless of whether those options are best for the customer.
A third area of focus involves the conditions Amazon sets for sellers who want access to promotional events like Prime Day. There are indications that participation – and the traffic boost that comes with it – may be tied to sellers agreeing to pricing terms or service commitments that effectively push them deeper into Amazon’s ecosystem. For smaller sellers, declining those terms can mean being sidelined during the highest-traffic periods of the year.
The investigation falls under the EU’s Digital Markets Act, the bloc’s landmark legislation designed specifically to regulate large tech platforms designated as “gatekeepers.” Amazon was formally designated a gatekeeper under the DMA, which means it faces stricter obligations around how it treats third-party businesses that rely on its infrastructure. A violation finding under the DMA can carry fines of up to 10 percent of global annual turnover.
The Pressure Building on Amazon’s Marketplace Model
Amazon’s marketplace is not a side business. Third-party sellers now account for more than half of all units sold on the platform, and the fees Amazon collects from those sellers – including referral fees, fulfillment charges through FBA, and advertising costs – represent one of the company’s fastest-growing revenue streams. That financial dependency cuts both ways: sellers need Amazon’s reach, and Amazon needs sellers to fill a catalog no single retailer could maintain on its own.
That mutual dependency is exactly why the power imbalance is so difficult to address through market forces alone. A seller who protests Amazon’s fee structures or algorithmic treatment faces a stark choice: absorb the disadvantage or abandon the most trafficked retail platform in most of the markets where they operate. Many sellers report spending more on Amazon advertising year over year not because it is more effective, but because visibility on organic search results within the platform has declined as paid placements have expanded.
This is not Amazon’s first encounter with European antitrust scrutiny. In 2022, the company reached a settlement with the European Commission over similar concerns about seller data and Buy Box preferencing, agreeing to a set of behavioral remedies that were supposed to create fairer conditions. Regulators now appear to believe those remedies did not go far enough – or that Amazon’s compliance has been incomplete. A formal DMA investigation signals a willingness to move beyond negotiated settlements and toward binding obligations with real financial consequences.
Meanwhile, Amazon continues to expand the services it sells to marketplace participants. Logistics, warehousing, advertising, lending, and even insurance products are now part of the Amazon ecosystem available to sellers. Each additional service deepens the relationship and creates more data touchpoints. The argument from Amazon’s side is that these services genuinely help sellers grow – and by most accounts, many sellers do grow using them. The concern from regulators is whether sellers have any meaningful choice in the matter, or whether opting out quietly tanks their performance metrics. For context on how digital giants are navigating advertiser and partner relationships under scrutiny, Amazon’s situation shares some structural DNA with Meta’s ongoing tensions over how its platform serves the businesses that fund it.
The DMA investigation timeline is not fixed, but these proceedings typically run for at least 12 months before a formal finding. During that period, Amazon will have the opportunity to submit evidence and propose remedies. The Commission can also impose interim measures if it determines that urgent action is needed to prevent serious harm – a provision that gives regulators leverage before a final ruling.
What It Means for Sellers and the Broader Market
For the hundreds of thousands of third-party sellers currently operating on Amazon’s European marketplaces, the investigation does not change day-to-day operations yet. But a finding against Amazon could mandate structural changes to how the Buy Box works, how seller data is stored and used, and what conditions Amazon can attach to promotional access. Those changes, if they materialize, could rebalance the visibility and cost dynamics that currently shape every pricing and inventory decision a marketplace seller makes.
The broader question is whether regulatory pressure can actually shift the economics of a platform that has spent two decades optimizing for its own growth. Amazon has demonstrated repeatedly that it can absorb fines and compliance costs while maintaining its competitive position. The DMA was written with that history in mind – which is why its penalty structure is tied to global revenue rather than European revenue alone. Whether the threat of a multi-billion euro fine is enough to change behavior at the algorithmic level, or whether Amazon will treat compliance as a minimum-bar exercise while preserving the structural advantages it has built, is the real test the investigation will ultimately put to the company.
Frequently Asked Questions
What is the EU investigating Amazon for?
The EU is probing whether Amazon unfairly uses third-party seller data, manipulates Buy Box placement to favor its own products, and ties promotional access to conditions that push sellers into its paid services.
What penalties could Amazon face under the Digital Markets Act?
Under the DMA, Amazon could face fines of up to 10 percent of its global annual turnover if found in violation, which would amount to billions of euros.
