About $1.3 Billion Dark-Pool Block of BlackRock’s IBIT Traded as Bitcoin Fell

A roughly $1.3 billion off-exchange block trade in BlackRock’s iShares Bitcoin Trust surfaced Tuesday morning as Bitcoin fell and U.S. spot Bitcoin ETFs logged a day of net outflows, underscoring how large institutional crypto trades are now moving through mainstream ETF market plumbing.

The trade involved about 29.2 million shares of IBIT, BlackRock’s U.S. spot Bitcoin ETF, and was reported as executed at about 10:30 a.m. ET on May 26. Bloomberg ETF analyst Eric Balchunas said the shares changed hands at roughly $43.16 each, implying a value of about $1.26 billion, commonly rounded to $1.3 billion. The transaction was executed in a dark pool, a private trading venue where institutions can move large blocks off-exchange rather than through the public order book. The seller and counterparty were not publicly identified.

The print was flagged publicly by Alex Thorn, head of firmwide research at Galaxy Digital, and Balchunas later confirmed the size and timing. Bitcoin fell about 1.4% to 1.5% in the roughly 10 minutes after the reported trade and later hovered near a 24-hour low around $75,600, according to market snapshots cited in coverage. At the same time, U.S. spot Bitcoin ETFs posted about $333 million to $334 million in net outflows on May 26, according to data cited from SoSoValue. IBIT accounted for about $192.4 million of those redemptions. The timing is notable, though the trade’s coincidence with the price drop and ETF outflows does not by itself show it caused either move.

Balchunas said the ETF itself showed little sign of strain despite the size of the block. “Confirmed.. 29 million share trade ($1.3b) of $IBIT executed at 1030am this morning. This screen shows all the IBIT trades today by size and you can see one of these is not like the others. Price unchanged today so mkt absorbed it well,” he wrote on X, as quoted by Decrypt. Thorn described it as a “massive $1.289 billion IBIT block sale by unknown party through dark pool at 10:30am today, biggest such trade i’ve ever seen.”

IBIT launched on Nasdaq on Jan. 11, 2024, and by late May 2026 had grown into the largest U.S. spot Bitcoin ETF, with roughly $61 billion in assets under management, based on market-data snapshots. That scale helps explain how a trade this large could be executed without a severe dislocation in the fund itself, even as the underlying cryptocurrency weakened.

Dark pools are commonly used by institutional investors that want to trade large positions without telegraphing the full order to the wider market before execution. The trades are reported after the fact, but the counterparties typically are not disclosed.

That leaves a central fact unresolved: A billion-dollar block of the biggest U.S. spot Bitcoin ETF changed hands through a private venue, and the public still does not know who sold it or who bought it. For a secondary-market ETF trade like this one, no public issuer filing would typically be expected.