Amazon faced a setback in the UK when the Court of Appeal denied its request to overturn the certification of two mass lawsuits that could claim up to £4 billion in damages. The decision leaves the cases, brought by retailers and consumers, in the legal system.

Andreas Stephan, a competition law academic, leads the retailer claim, representing more than 200,000 third‑party sellers and seeking up to £2.7 billion. He alleges Amazon manipulates the Buy Box feature to favor its own logistics centres and delivery network. Separately, consumer advocate Robert Hammond pursues a case worth up to £1.3 billion.

Amazon has long argued the claims lack merit, citing flawed economic methodology and challenging the early certification step. The Competition Appeal Tribunal certified both cases last year on an opt‑out basis, meaning all members of the claimant class are included unless they opt out. Amazon sought to appeal that certification.

The ruling keeps the lawsuits alive, potentially exposing Amazon to significant financial exposure and regulatory scrutiny. Investors may reassess the company’s competitive practices, while retailers and consumers await the court’s next move. Amazon has not yet issued a statement on the outcome.