Billionaires Are Buying a BlackRock Index Fund That Could Soar Up to 73,000%, According to Wall Street Experts In the first half of 2024, the billionaires listed below started positions in BlackRock's exchange-traded fund (ETF) that tracks the spot price of Bitcoin (CRYPTO: BTC). The fund is called the iShares Bitcoin Trust (NASDAQ: IBIT). Their positions remain small, but their ownership is still noteworthy because they manage the three best-performing hedge funds in history as measured by net gains, according to LCH Investments.