BlackRock's IBIT dominance continues to grow. | Credit: Stephanie Keith via Getty Images. Key Takeaways BlackRock holds $92.66 billion in BTC, more than half of the combined net assets of all U.S. spot Bitcoin ETFs. Grayscale has recorded$24.62 billion in net outflows since launching in January 2024. Without BlackRock, BTC ETF flows would be running negative overall. U.S. spot Bitcoin (BTC) exchange-traded funds (ETFs) have been a roaring success, though mostly for BlackRock, which has been domin ...