According to a 13F filing with the Securities Exchange Commission (SEC), the size of spot bitcoin ETFs held by large institutions such as pension funds or hedge funds tripled in the fourth quarter of 2024. As of Q4 2024, institutional investors held $38.70 billion worth of spot Bitcoin ETFs. This figure is more than three times that of Q3, which reported holdings of just $12.40 billion. Among them, the Wisconsin Investment Commission increased its holdings in BlackRock iShares Bitcoin Trust (IBIT) to just over 6 million shares. Billionaire hedge fund investor Paul Tudor also nearly doubled his holdings in IBIT from 4,428,230 to 8,048,552 shares. According to Eric Balchunas, senior ETF analyst at Bloomberg Intelligence, IBITs currently have 1,100 institutional holders reporting their holdings through the 13F filing, while most new ETFs typically have fewer than 10 institutional holders.