Abu Dhabi sovereign wealth fund, Citadel Advisors boost BlackRock Bitcoin ETF holdings

Key Takeaways

• Mubadala Investment Company increased its holdings in BlackRock's spot Bitcoin ETF to 8.7 million shares valued at $408 million.
• Citadel Advisors expanded its IBIT holdings to over 3 million shares worth approximately $147 million.

New SEC filings reveal that Abu Dhabi’s Mubadala Investment Company and Citadel Advisors have increased their holdings in BlackRock’s spot Bitcoin ETF, the iShares Bitcoin Trust (IBIT), a sign of sustained institutional interest in crypto-related assets despite recent market volatility.

Mubadala Investment Company, Abu Dhabi’s sovereign wealth fund, increased its holdings in BlackRock’s spot Bitcoin ETF to 8.7 million shares valued at $408 million as of March 31, according to a Thursday filing .

This represents an uptick from the 8.2 million IBIT shares held at the end of last year. However, the total value of the holdings fell from $436 million to $408 million due to a decline in the share price.

Between December 31, 2024, and March 31, 2025, IBIT’s share price dropped from around $54 to approximately $47, according to Yahoo Finance data . The ETF’s shares closed Thursday down slightly at $58.

Citadel Advisors also expanded its IBIT position in Q1 2025. According to a Thursday filing , the firm held over 3 million IBIT shares worth approximately $147 million, up from around 1 million shares in December.

In addition, Citadel Advisors reported holding $676 million in call options and $366 million in put options tied to IBIT.

Mubadala and Citadel Advisors join other major institutional investors, including Goldman Sachs and Avenir Group , in expanding their IBIT exposure. However, not all large holders are increasing their stakes.

The State of Wisconsin Investment Board exited its entire $321 million position in BlackRock’s Bitcoin ETF, according to a recent SEC filing. Despite the divestment, the board still holds crypto-related assets, including nearly $19 million in Coinbase stock.

Millennium Management, previously the largest IBIT holder, on Thursday reported owning about 17.5 million shares as of March 31, valued at approximately $823 million. This is down from the 29.8 million shares worth $1.5 billion disclosed in its February filing .

Millennium’s new filing also revealed options exposure to IBIT, including $11.5 million in call options and $12.5 million in put options.

Millennium remains one of IBIT’s top shareholders. According to the latest data tracked by Fintel, the firm is the second-largest institutional holder, behind Goldman Sachs. Citadel ranks third, followed by other major stakeholders such as Capula Management and D.E. Shaw Co.