The Association of Consumer Support Organisations (ACSO) has launched opt-out collective proceedings against Amazon on behalf of millions of UK consumers. 

The association is seeking to represent over 45m consumers in its proceedings, alleging that the online retailer’s pricing policies have led to higher prices for consumers buying goods from third-party sellers on its UK marketplace.

ACSO filed its application for a collective proceedings order with the UK’s Competition Appeal Tribunal on 14 August.

The claim is being launched on an opt-out basis, meaning that all eligible consumers are automatically included in the claim. 

Any UK consumer who purchased from a third-party seller on Amazon’s UK marketplace between August 2019 and August 2025 is included as a proposed class member. 

ACSO claims Amazon’s pricing policies prevented third-party sellers from offering lower prices for their products elsewhere on the internet. 

The membership organisation alleged that these policies protected Amazon from healthy price competition from other e-commerce platforms, allowing it to charge sellers higher fees, which UK consumers ended up paying for in the form of higher prices on Amazon.

Amazon’s pricing policies were investigated by the UK Competition and Markets Authority (formerly the Office of Fair Trading) in 2012, the German Federal Cartel Office in 2013 and the Japan Fair Trade Commission in 2016. 

Following each of these investigations, the ecommerce giant committed to ceasing its anti-competitive conduct. 

However, ACSO alleges Amazon circumvented those commitments by launching its current pricing policies, which remain in place today.

The German Federal Cartel Office and the Japan Fair Trade Commission are now investigating Amazon’s current price parity policies, with the Canadian Competition Bureau also examining them.

ACSO founder and executive director Matthew Maxwell-Scott said: “Millions of people in the UK make purchases on Amazon every day. 

“Despite the company’s assurances that it is above all else ‘customer-obsessed’, we consider there are strong grounds to argue that UK consumers have paid higher prices because of Amazon’s pricing policies.”

He continued: “ACSO is therefore bringing collective proceedings against Amazon to ensure that consumers can obtain redress for the considerable losses they have suffered.

“Collective actions such as these are an excellent way for consumers to exercise their rights and for anti-competitive corporate behaviour to be challenged.”

In June, Amazon came bottom of the Groceries Code Adjudicator’s (GCA) supplier compliance rankings for the third year running, with more than one in three of its grocery suppliers reporting that it rarely or never complied with the industry’s fair treatment rules.

The GCA’s annual survey found that only 66% of the online giant‘s suppliers felt the company consistently or mostly followed the Groceries Code, which governs fair dealings between retailers and their suppliers, The Times reported.

Amazon responded to Retail Gazette’s request for a statement the following day (19 August). The article can be found here.

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