Elon Musk has expanded his lawsuit against OpenAI to include antitrust claims, accusing the company and its largest financial backer, Microsoft, of monopolizing the generative AI market to the detriment of competitors like Musk's xAI. The amended lawsuit, filed in federal court in California, alleges that OpenAI, initially founded as a nonprofit dedicated to safe AI development, has shifted towards a for-profit model largely influenced by Microsoft's substantial investment of over $13 billion. Musk accuses OpenAI's CEO Sam Altman and other founders of prioritizing profits over their original mission to benefit humanity and claims that OpenAI and Microsoft have discouraged investors from funding rival firms. The lawsuit also names LinkedIn co-founder Reid Hoffman and Microsoft executive Dee Templeton as additional defendants, and former OpenAI board member Shivon Zilis as a plaintiff, representing Musk's interests. OpenAI has dismissed the lawsuit as baseless, asserting that it remains committed to its mission of developing AI for the public good. The legal battle underscores Musk's continuing opposition to OpenAI’s current trajectory and its partnership with Microsoft.