Elon Musk has launched xAI’s Grok 4—calling it the “world’s smartest AI” and claiming it can ace Ph.D.-level exams and outpace rivals such as Google’s Gemini and OpenAI’s o3 on tough benchmarks

Elon Musk's AI venture, xAI, has lost one of its top engineering leaders to rival AI heavyweight OpenAI. Uday Ruddarraju, who played a pivotal role in building the core infrastructure of Musk's xAI, confirmed his exit recently.