A London tribunal has cleared a £2.1 billion ($2.8 billion) collective lawsuit against Microsoft to proceed to trial, putting fresh pressure on the company’s cloud licensing practices as regulators intensify their scrutiny of the market.
The case alleges Microsoft overcharged nearly 60,000 UK businesses for using Windows Server software on rival cloud platforms including Amazon Web Services, Google Cloud, and Alibaba Cloud. Competition lawyer Maria Luisa Stasi brought the claim on behalf of affected organizations, arguing that Microsoft’s licensing structure made Azure appear cheaper by raising costs for running identical workloads on competing services.
London’s Competition Appeal Tribunal certified the case to move forward after rejecting Microsoft’s argument that it should be dismissed. A company spokesperson said they plan to appeal against the tribunal's decision.
The tribunal did not rule that Microsoft broke competition law but determined the claim was fit to proceed toward trial.
During hearings last year, Microsoft defended its vertically integrated business model, stating that using Windows Server as an input for Azure while also licensing it to rivals can benefit competition. The company argued Stasi’s case failed to present a workable method for calculating alleged losses and should be thrown out.
Authorities in Britain, Europe, and the United States are all investigating how major technology firms operate in the rapidly expanding cloud sector.
Last July, an inquiry group from Britain’s Competition and Markets Authority concluded that Microsoft’s licensing practices reduced competition for cloud services “by materially disadvantaging AWS and Google.” The company responded at the time that the report ignored how “the cloud market has never been so dynamic and competitive.”
The CMA announced earlier this year it plans to launch a Strategic Market Status investigation into Microsoft’s business software ecosystem in May 2026, with cloud licensing concerns explicitly included in that work.
“an important moment for the thousands of organizations impacted by Microsoft’s conduct.”
Stasi described the tribunal’s decision as such. The ruling keeps alive one of the largest collective actions against a technology company in UK history while regulatory bodies continue parallel examinations of similar market dynamics.
