Litigation boutique Hausfeld & Co has filed a group action claim against technology giant Google on behalf of 19.5 million eligible U.K. users in the country’s Competition Appeal Tribunal.

The claim alleges that Google unfairly restricts consumers from accessing potential competition from other app distributors by requiring smartphone manufacturers to pre-install a bundle of Google’s proprietary apps and services including the Google Play Store as well as imposing other contractual and technical restrictions.