Competition tribunal selects Prof Stephan's claim against Amazon over BIRA's case

On January 20, 2025, the Competition Appeal Tribunal (CAT) ruled in favor of Professor Andreas Stephan's collective proceedings application against Amazon over a competing claim from BIRA Trading Limited. According to the judgment, Prof Stephan will lead a class action representing over 200,000 UK-based merchants who sold products on Amazon's UK marketplace.

The case centers on alleged anti-competitive practices by Amazon between 2015 and 2024. The tribunal had to determine which of two competing applications should proceed to a certification hearing in what is known as a "carriage dispute."

According to the judgment, Prof Stephan's claim encompasses five distinct forms of alleged abuse by Amazon: the misuse of non-public seller data, self-preferencing of Amazon Retail in the Buy Box feature, favoring sellers using Fulfillment by Amazon (FBA) over those using their own fulfillment methods, conditioning access to Prime status on using FBA services, and anti-discounting practices that discouraged sellers from offering lower prices elsewhere.

In contrast, BIRA's claim focused more narrowly on two allegations - Amazon's use of non-public data and self-preferencing in the Buy Box, specifically related to Amazon's product entry decisions. The tribunal found Prof Stephan's broader scope "more consistent with the goals of access to justice by capturing more viable claims."

The methodological approach proposed by Prof Stephan's expert, Dr. George Houpis of Frontier Economics, also proved more compelling to the tribunal. Dr. Houpis presented an algorithmic method that would attempt to recreate Amazon's decision-making processes absent the alleged anti-competitive elements, complemented by econometric analysis. The tribunal found this more robust than BIRA's methodology.

The case builds on several regulatory investigations into Amazon's marketplace practices. In November 2023, the UK Competition and Markets Authority accepted binding commitments from Amazon following concerns about its use of third-party seller data and Buy Box preferences. Similar investigations by the European Commission resulted in commitments covering the French, German and Spanish markets in December 2022.

The Italian competition authority had previously fined Amazon €1.3 billion in December 2021 over allegedly unfair practices favoring sellers using FBA services. Separately, the US Federal Trade Commission launched proceedings against Amazon in September 2023, with an amended complaint in March 2024 alleging the company punishes sellers who offer lower prices on other platforms.

The tribunal's decision means Prof Stephan's case will proceed to a certification hearing to determine if it can continue as a collective action. The BIRA proceedings have been stayed but could be revived if Prof Stephan's certification attempt fails.

The ruling provides important guidance on how the UK competition tribunal evaluates competing collective proceedings applications. Rather than favoring the first claim filed, the tribunal conducts a multi-factor assessment focusing on which case would best serve the interests of class members while remaining manageable and cost-effective.

Looking ahead, if certified, Prof Stephan's proceedings could potentially be heard alongside a parallel consumer class action led by Robert Hammond, which alleges Amazon's practices led to higher prices for shoppers. The tribunal noted the advantage of both cases using similar methodological approaches if heard together.

The case represents one of the largest collective proceedings yet brought under the UK's competition regime. The broad scope of Prof Stephan's claim, encompassing multiple forms of alleged abuse affecting hundreds of thousands of merchants over nearly a decade, underscores the increasing complexity of competition enforcement in digital markets.