Massive $1.26 Billion IBIT Block Sale Likely Driven by Investor Exit, Not Bitcoin Basis Trade

A massive $1.26 billion block sale of BlackRock’s iShares Bitcoin Trust (IBIT) has sparked discussion across the crypto market, with new analysis suggesting the transaction was driven by a large investor seeking a fast exit from bitcoin exposure rather than the unwinding of a bitcoin basis trade.

According to crypto investment firm NYDIG, the transaction took place on May 26, when approximately 29.21 million IBIT shares were sold off-exchange at $43.16 per share. The sale was completed at a $1.01 discount to IBIT’s market price of $44.17, representing a 2.3% discount and roughly $29.5 million in execution costs.

The trade was reported through the FINRA/Nasdaq TRF Carteret facility, a platform commonly used for privately negotiated off-exchange block transactions. NYDIG noted that the sizable discount indicates the seller prioritized speed and certainty over achieving the highest possible sale price.

Some analysts initially speculated that the transaction could be linked to a bitcoin basis trade, a strategy that involves holding spot bitcoin exposure while simultaneously shorting bitcoin futures contracts. However, NYDIG dismissed this theory, arguing that the significant discount would have materially reduced the profitability of such a strategy.

The firm also examined activity in CME bitcoin futures markets. The IBIT position represented exposure comparable to roughly 3,700 CME bitcoin futures contracts. Despite this, only 91 futures contracts traded during the minute the block sale occurred, with no unusual increase in trading volume.

NYDIG’s Global Head of Research, Greg Cipolaro, stated that the size of the transaction, the 2.3% discount, the absence of corresponding CME futures activity, and the limited number of potential sellers all suggest the sale was not a contemporaneous basis-trade unwind.

The large IBIT transaction comes amid continued pressure on U.S. spot Bitcoin ETFs. Data from SoSoValue shows that spot bitcoin ETFs recorded net outflows on every trading day between May 15 and May 29. During the same period, total assets held by these funds declined from $107.75 billion to $94.17 billion.

Meanwhile, bitcoin has faced a challenging year, with its price falling 16% as investors continue moving capital away from crypto assets. In contrast, traditional markets, including equities and commodities, have experienced stronger performance and attracted increasing investor interest. The latest IBIT block sale highlights ongoing shifts in investor sentiment and may signal continued caution toward bitcoin ETFs and the broader cryptocurrency market in 2026.