The UK Competition Appeal Tribunal (CAT) has begun deliberations on a £2.1 billion class-action lawsuit against Microsoft. The CAT will decide if the case, brought on behalf of nearly 60,000 UK businesses, proceeds to a full trial.
Plaintiffs accuse Microsoft of anti-competitive behavior by overcharging for Windows Server software licenses used on rival cloud platforms. This practice allegedly pushes customers toward Microsoft’s own Azure service, away from competitors like Amazon Web Services and Google Cloud.
The lawsuit alleges these licensing practices constitute an "abusive strategy" designed to maintain cloud market dominance. This challenge follows a separate investigation by the UK Competition and Markets Authority (CMA), which concluded this year that Microsoft’s licensing practices adversely impact competition. Microsoft argues the case should be dismissed, stating that offering its software on competing platforms demonstrates healthy competition.