Amazon, Microsoft Must Face Tougher UK Antitrust Probe, CMA Says

Microsoft Corp. and an Amazon Web Services Inc.’s dominance in the cloud services market must face an antitrust investigation under the UK’s new rules for digital markets, the country’s watchdog said after a 21-month long investigation.

The Competition and Markets Authority said that concerns over market dominance and lack of consumer choice at Microsoft and AWS should be investigated under its strategic market status rules.

With the watchdog’s digital market unit, the CMA can launch a probe to designate a company as having strategic market status and can eventually impose conduct requirements on firms. The watchdog can also hand out hefty fines and impose strict remedies to boost competition.

The decision adds to the increasing scrutiny the tech giants face under the UK’s tougher rules that came into effect this year. The decision comes on the heels of the CMA’s decision last week to deepen its probe into Apple Inc. and Google’s dominance over mobile ecosystems and a month after it intensified its investigation over Google’s online search and advertising business.

The CMA “misses the mark again,” a Microsoft spokesperson said in a statement. The cloud market is dynamic and competitive and the “recommendations fail to cover Google, one of the fastest-growing cloud market participants.”

The market for cloud infrastructure services for storage and computing resources, which allow businesses to avoid owning costly hardware and software, is “highly concentrated,” according to the CMA.

Microsoft and AWS held about a third of the market each in 2024, the CMA said. Google, the third largest provider, had about 5% to 10%. Cloud service customers spent £10.5 billion ($13.9 billion) in 2024, with spending growing by nearly 30% each year since 2020, according to the CMA.

“Swift action from,” the CMA “is essential to ensure British businesses pay a fair price and to unleash choice, innovation and economic growth in the UK,” Chris Lindsay, a vice president at Google Cloud, said.

Microsoft had significant market power in relation to its software products and its licensing practices have an adverse impact on cloud services market, the regulator said.

The proposed action is “unwarranted,”’ AWS said. “It risks making the UK a global outlier at a time when businesses need regulatory predictability for the UK to maintain international competitiveness.”

The CMA anticipates that the decision to refer the investigation under digital rules would be considered by its board in early 2026.