Anthropic Gains Ground as ChatGPT Faces User Exodus Following Pentagon Agreement Controversy

Anthropic has overtaken ChatGPT to become the top-ranked free application in the US iOS App Store following a mass migration of users away from OpenAI. Industry sources indicate the shift accelerated after Anthropic declined to provide the US Department of Defense with access to its AI models for mass domestic surveillance operations and autonomous weapons development. This refusal prompted President Trump to issue an executive order mandating all federal agencies cease using Anthropic products while Defense Secretary Pete Hegseth revealed plans to classify the company as a national supply chain risk. In contrast OpenAI secured its own defense contract with the Pentagon shortly thereafter a deal that has generated substantial controversy. According to data from Anthropic daily user registrations have reached unprecedented levels with free-tier users increasing by over 60% since January 2026 and paid subscriber numbers more than doubling year-over-year.