Proton Mail developer sues Apple in U.S., says App Store model breaks antitrust laws

Privacy-focused Swiss tech company Proton, best known for its encrypted email service Proton Mail, is suing Apple in the United States on behalf of “millions” of developers around the world. Here are the details.

The proposed class action, filed Monday in California (via Reuters), claims Apple has: “eliminated competition and extracted supracompetitive profits from app developers through a web of exclusionary conduct.”

Proton says the lawsuit represents millions of iOS developers who are subject to what it calls Apple’s “stranglehold” over how apps are distributed and how payments are processed on iOS, and requests
a jury trial to decide the claims.

The complaint also describes Apple’s dominance as a system that:

“Suppresses competition, obstructs innovation, and deprives consumers of meaningful choices in privacy-respecting technologies.”

The case focuses on two key markets: iOS app distribution and iOS in-app payment processing

Proton argues that Apple’s rules, such as the mandatory use of its in-app purchase system, the ban on alternative app stores, and commission rates of up to 30%, violate U.S. antitrust law.

Proton is asking the court to force Apple to allow competing app stores and payment processors on iOS, and to award monetary damages for the alleged high fees and business restrictions developers have faced for years:

“This lawsuit seeks to restore competition to the iOS app distribution and payment processing markets through injunctive relief that would allow competing app stores and payment processors to serve iOS users. This action also seeks monetary damages for developers for the harm suffered from Apple’s illegal monopolization, including the excessive commissions it has been forced to pay and the lost opportunities for innovation and growth.”

The filing comes just days after Apple announced sweeping App Store rule changes in the EU, including support for multiple external links, third-party payment providers, and new fee structures for developers. These changes, however, do not apply to the U.S. App Store. Apple has also made clear it’s not thrilled with the European Commission’s demands, stating that:

“The European Commission is requiring Apple to make a series of additional changes to the App Store. We disagree with this outcome and plan to appeal.”

The case is Proton AG v. Apple Inc., No. 4:25-cv-05450. We’ve reached out to Apple for comment and will update this post if we hear back.