"BlackRock owns less than 0.5 per cent of xAI and they are one of many investors," Mr. Musk tweeted. Previously, Musk's AI company xAI announced the completion of $6 billion Series C financing, anchor including a16z, BlackRock, Fidelity Management & Research Company, Kingdom Holdings, Lightspeed, MGX, Morgan Stanley, OIA, QIA, Sequoia Capital, Valor Equity Partners and Vy Capital.