Large holder dumped 29.21 million BlackRock Bitcoin ETF shares at 2.3% discount on May 26
A $1.26 billion off-exchange block trade in BlackRock’s IBIT spot Bitcoin ETF on May 26 was most likely a large directional holder exiting a concentrated position rather than a basis-trade unwind, according to NYDIG, a cryptocurrency research firm.
The block trade involved 29.21 million IBIT shares sold at $43.16 per share, representing approximately 18,500 BTC of exposure. The seller accepted a $29.5 million discount, or $1.01 per share below the prevailing market price of $44.17 at the time of execution.
NYDIG published its analysis on May 29 in a weekly Bitcoin digest. Greg Cipolaro, Global Head of Research at NYDIG, stated: “The evidence is most consistent with a large directional holder exiting a concentrated position rather than a contemporaneous basis-trade unwind.”
The transaction exceeded the reported position of every disclosed March 31, 2026, 13F holder, according to NYDIG. The firm noted that the block trade “required an unusually large price concession, and was not accompanied by the CME futures activity that would be expected if a basis position were being unwound.”
The trade executed at 10:30:34 ET through FINRA/Nasdaq TRF Carteret, a facility for privately negotiated off-exchange trades. It was marked with a Rule 611 trade-through exemption and designated as an Intermarket Sweep Order, indicating a negotiated block prioritizing execution certainty over price improvement. A 20,000-share trade printed seconds earlier at $44.17, confirming the $43.16 price was specific to the block.
NYDIG ruled out a simultaneous basis unwind by analyzing CME Bitcoin futures volume. “A simultaneous basis unwind of this size would have represented approximately 43% of total daily CME volume and likely produced a visible spike in futures activity. No such activity occurred,” NYDIG said. CME Bitcoin futures volume that day totaled 8,630 contracts, with only 91 contracts in the 10:30–10:31 interval and 1,070 contracts in the 10:30–11:00 window.
The block trade occurred during a broader period of ETF outflows. Spot Bitcoin ETFs experienced six consecutive sessions of net outflows beginning May 15, totaling $1.55 billion through May 26. IBIT accounted for $1.1 billion of those outflows.
Bitcoin price action provided additional context. The asset had rallied into a descending 200-day moving average near $82,000–$82,500 in early May but failed to break through. By mid-May, Bitcoin had fallen below the 200-day trendline, with the 14-day RSI sliding from around 70 to the mid-30s. At the time of the block trade, Bitcoin was trading near $72,891.
IBIT rebounded to $44.06 within one minute after the block trade. Volume in IBIT had accelerated sharply before the block, with 822,000 shares trading in the 10:26–10:27 interval and 702,000 shares in 10:27–10:28, approximately three to four times normal activity.
NYDIG cautioned against reading IBIT’s reported $720 million net redemptions across May 26–27 as a direct measure of the block trade. ETF creations and redemptions can obscure simultaneous gross activity, the firm noted. IBIT’s reported NAVs on those dates were $42.955 on May 26 and $42.431 on May 27.
“The designations indicate a negotiated off-exchange block transaction executed under trade-through exemptions and sweep procedures that allowed the seller to prioritize certainty of execution over price improvement,” NYDIG said.
