Elon Musk’s X and xAI initiated legal action against Apple and OpenAI on Monday, accusing the tech giants of anticompetitive collusion. The lawsuit claims Apple is attempting to safeguard its smartphone monopoly by partnering with OpenAI, a leading company in generative AI chatbots, to integrate ChatGPT into Apple’s systems.

The legal challenge is the latest development in the ongoing conflict between Musk and Sam Altman. Musk, a former co-founder and co-chair of OpenAI, has previously sued to prevent OpenAI from transitioning into a for-profit entity and made an unsuccessful $97.4 billion bid to acquire the company.

Earlier this month, Musk publicly accused OpenAI and Apple of anticompetitive practices on X, stating that it’s “impossible for any AI company besides OpenAI to reach #1 in the App Store.”

Apple and OpenAI announced their partnership in June, with collaborative features anticipated to be released in December. As of press time, neither Apple nor OpenAI had responded to requests for comment regarding the lawsuit.