A British consumer advocacy group has launched a $3.8 billion antitrust class action against Apple on behalf of its 40 million U.K. customers alleging the U.S. tech giant is fleecing them by locking them into iCloud.

A consumer rights group in the U.K. has filed a lawsuit against Apple, claiming it locks its customers into the iCloud cloud storage service.

Apple encouraged its users to sign up to iCloud to store photos, videos and other data while making it difficult to use alternative providers. Customers then had to pay for the service once their data exceeded the free 5GB limit,

The UK's "Which?" consumer group and publication is to sue Apple over what it claims is the company's anti-competitive way of locking users into paying for iCloud storage.

Apple Inc faces a lawsuit from a UK consumer group over allegations its monopoly on data storage breaches competition law, in a fresh class action that could ultimately cost the tech giant billions.