U.S. spot Bitcoin (BTC) ETFs have attracted approximately $2.8 billion in net inflows over the past five trading sessions, helping push Bitcoin’s price from around $85,000 to $94,000. The iShares Bitcoin Trust (IBIT) led the charge, accounting for $1.3 billion of those inflows.

Michael Saylor, Chairman of MicroStrategy (MSTR) — the largest publicly traded corporate holder of Bitcoin — predicted during the Bitcoin Standard Corporation’s Investor Day that “IBIT will be the biggest ETF in the world within ten years.”

Currently, IBIT holds a market capitalization of $54 billion and recorded more than $1.5 billion in trading volume on Thursday. For context, the Vanguard S&P 500 ETF (VOO), the world’s largest ETF by market cap, is valued at $593.5 billion — more than ten times IBIT’s size.

Eric Balchunas, Senior ETF Analyst at Bloomberg, acknowledged the potential for IBIT to overtake VOO, but noted the extraordinary conditions required for it to happen.
“It’s possible, particularly if IBIT begins consistently absorbing more capital than VOO,” Balchunas said. “However, this would demand daily inflows well above $1 billion — ideally closer to $3 to $4 billion — to make meaningful progress. Extraordinary circumstances would need to align, but it’s not impossible.”

Meanwhile, the annualized basis trade for Bitcoin ETFs — where investors go long spot ETFs and short CME Bitcoin futures — has risen sharply to nearly 10%, up from 5% at the start of April. A 2,000 BTC increase in futures open interest over the past week suggests that a significant share of recent ETF inflows could be attributed to basis trading rather than purely directional investment bets.