xAI

xAI is a frontier AI lab founded by Elon Musk in 2023 to build the Grok family of large language models, trained on its Colossus supercomputer in Memphis. In March 2025 xAI acquired X Corp (the social network formerly known as Twitter) in an all-stock deal, combining the two under X.AI Holdings. In February 2026 SpaceX agreed to acquire xAI in an all-stock transaction; xAI was folded into SpaceX as its AI division in May 2026. On June 12, 2026, parent SpaceX completed the largest IPO in history — pricing at $135 per share to raise roughly $75B at a ~$1.77T valuation — and began trading on Nasdaq as SPCX, making xAI part of a publicly listed entity.