Elon Musk has accused Apple of unfairly favouring OpenAI’s ChatGPT in its App Store rankings. He warned that his artificial intelligence company, xAI, would pursue legal action.

In a post on X, Musk alleged that Apple was making it impossible for any AI company other than OpenAI to reach the top spot in the App Store. He described this as “an unequivocal antitrust violation.” Musk provided no evidence to support the claim.

The remarks came as tensions between Musk and OpenAI intensified. Users on X quickly noted that China’s DeepSeek AI and Perplexity AI had recently reached the number one spot in the App Store in different markets, contradicting Musk’s claim.

DeepSeek and Perplexity both compete directly with OpenAI’s ChatGPT and Musk’s Grok.

OpenAI CEO Sam Altman responded to Musk’s accusations on X, calling them “remarkable.” He alleged that Musk had been accused of manipulating X’s algorithm to benefit his own companies and harm competitors. Musk fired back, calling Altman a “liar.”

Altman then challenged Musk to sign a sworn statement declaring he had never ordered changes to X’s algorithm to harm rivals or help his own firms.

The public dispute came days after both OpenAI and xAI rolled out updated versions of their AI assistants. ChatGPT held the top position in the App Store’s free iPhone app rankings on Tuesday, while Grok was in fifth place.

Apple has not publicly commented on the dispute. App Store rankings are influenced by factors such as download volume, user engagement, and reviews.

OpenAI and Apple have an existing partnership announced in June 2024. This collaboration is designed to integrate ChatGPT features into iPhones and other Apple devices. Last week, OpenAI said its ChatGPT-5 was available for free to its 700 million weekly users.

The latest flare-up between Musk and OpenAI is part of a long-running feud. Musk co-founded OpenAI in 2015 but left the company in 2018. Since then, he has repeatedly criticised its direction. In April 2025, OpenAI filed counterclaims against Musk, accusing him of waging a “relentless campaign” to harm the organisation. Court documents in California alleged Musk became hostile after leaving the company before its major successes.

OpenAI further claimed that Musk sought to build a competing AI venture to surpass OpenAI’s technological achievements, motivated by personal ambition. Musk launched xAI in 2023 as part of this effort.

The AI industry has become increasingly competitive since the launch of ChatGPT in late 2022. Major technology companies, including Amazon, Google, Meta, Microsoft, and xAI, have invested heavily to develop leading AI models.

Chinese startup DeepSeek gained global attention in early 2025 for producing a high-performance AI model that used less expensive chips. The company’s success disrupted industry dynamics, creating new competition for both OpenAI and xAI.

As of now, no formal legal action by xAI against Apple has been announced. The situation remains fluid, with significant commercial and legal implications for the AI and mobile app sectors.