BlackRock transferred 5,847 BTC and 26,269 ETH to Coinbase Prime on May 19, matching the largest IBIT redemptions of the year. The on-chain move points to imminent ETF-driven selling pressure on Bitcoin and Ethereum.
BlackRock transferred more than $504.9 million in Bitcoin (BTC) and Ethereum (ETH) to Coinbase Prime hot wallets on May 19, on-chain data from Arkham shows. The movement included 5,847 BTC valued at roughly $449.5 million from the iShares Bitcoin Trust (IBIT) and 26,269 ETH worth about $55.4 million from its Ethereum ETF entities. The transfer occurred in rapid batches, often in increments of 300 BTC for the Bitcoin portion.
The timing aligns with one of the largest single-day redemptions in IBIT’s history. The trust recorded $448 million in net withdrawals on May 18, part of broader U.S. spot Bitcoin ETF outflows exceeding $648 million that day. Ethereum ETFs also faced continued pressure, adding to multi-day redemption trends.
Deposits of this size to an exchange-linked custodian typically precede liquidity operations for spot ETFs. The simple read is that BlackRock is preparing to sell. A better market read involves the mechanics of ETF redemptions.
Arkham’s analysis tracked multiple transactions within a short window. The destination – Coinbase Prime – is the platform BlackRock uses for custody and to execute the creation and redemption cycle. The 5,847 BTC and 26,269 ETH represent a notable share of the funds’ holdings. IBIT’s total AUM is roughly $60 billion, so the movement equals about 0.8% of the fund’s Bitcoin.
When an authorized participant (AP) such as Jane Street or Citadel Securities redeems shares of IBIT, the ETF must deliver the underlying Bitcoin to the AP. The AP typically sells the coins on Coinbase Prime or another exchange to realise cash for their clients. BlackRock’s transfer is the operational step in that chain, not a proprietary decision to sell its own holdings.
The outflow from IBIT on May 18 was the largest since December 2024. It contributed to a weekly net outflow of roughly $600 million across all U.S. spot Bitcoin ETFs.
Redemptions of this magnitude create immediate selling pressure. The AP almost always liquidates the received Bitcoin in the open market. The transfer to Coinbase Prime gives traders a leading indicator: when the wallet moves to the exchange, a sale is likely within hours or days.
Bitcoin was trading near $78,000 at the time of the transfer, below the psychologically important $80,000 level. Continued outflows risk dragging BTC into the $72,000–$75,000 support zone.
The $448 million net withdrawal from IBIT on May 18 dwarfed typical daily flows. The fund’s previous large redemptions in 2025 rarely exceeded $200 million in a single session. The spike suggests either a single large holder redeeming or a coordinated move by multiple APs.
Ethereum, which has its own spot ETFs, saw $55.4 million in on-chain movement from BlackRock’s custodian addresses. ETH ETF outflows have been steady slower than Bitcoin’s. The transfer suggests APs are redeeming Ethereum ETF shares as well, potentially adding downside pressure on ETH relative to BTC. ETH was trading near $2,000 during the transfer.
The outflows do not tell the full story. IBIT has actually accumulated Bitcoin in May, despite the recent redemptions. The fund’s holdings increased from 810,800 BTC on May 1 to 818,840 BTC on May 19, a net addition of just over 8,000 BTC. Earlier in the month, IBIT’s holdings peaked at roughly 823,000 BTC before trimming 6,000 coins over the subsequent days through May 19.
The net dollar inflow for the month through May 19 stands at approximately $537 million.
| Metric | Value |
|---|---|
| Net BTC added from May 1 to May 19 | ~8,040 BTC |
| Peak holdings in early May | ~823,000 BTC |
| Holdings on May 19 | ~818,840 BTC |
| Net dollar inflow in May | ~$537 million |
This shows that BlackRock’s ETF was buying on dips earlier in May, then faced a sharp reversal of AP redemptions on May 18. The accumulation phase suggests institutional demand for Bitcoin remained robust at lower prices. The redemption event may reflect profit-taking or a tactical shift by investors who bought the ETF and now see BTC range-bound below $80K.
The timeline is clear: large redemptions in IBIT on May 18 triggered the Bitcoin transfer on May 19. The Ethereum transfer occurred concurrently. The next few trading sessions will determine whether this is a one-day event or the start of a sustained outflow period.
Traders should also monitor Coinbase Prime deposit addresses linked to BlackRock for further inflows. A second wave of large transfers would confirm that APs are still exiting. A halt would indicate redemptions have stabilised. BTC open interest on CME Bitcoin futures is a useful cross-check. A sharp decline would indicate hedge funds covering cash-and-carry positions, amplifying spot selling.
Spot Bitcoin and spot Ethereum are the most directly affected assets. The iShares Bitcoin Trust (IBIT) itself will see share price pressure if the underlying Bitcoin declines. Coinbase (COIN) stands to benefit from increased custody and trading revenues, its share price is more tied to overall crypto volumes. Broad crypto ETFs that hold both BTC and ETH may face correlated outflows if redemption pressure continues. Altcoins such as XRP, which recently re-entered the crypto chatter after a presentation by International Finance Bank on its role in financial infrastructure, could face collateral selling as market liquidity tightens across the board.
Execution risk is elevated during periods of high outflows. ETF APs typically sell Bitcoin in size, meaning limit orders on the bid side may get filled aggressively. Using midpoint or iceberg orders can reduce slippage. The $80,000 level on BTC has acted as resistance since early May. A break above that with the ETF flow backdrop would require a fundamental catalyst, not just technical support.
The BlackRock transfer also highlights the operational transparency of crypto ETFs. Unlike equity ETFs, where underlying transfers are opaque, Bitcoin ETF flows are visible on-chain. That transparency allows faster price discovery. It also increases the risk of front-running by high-frequency traders who monitor the same addresses.
For investors holding IBIT or the iShares Ethereum Trust, the key risk is not the transfer itself. It is the direction of AP redemptions. If the outflow trend reverses, the transfer will be a one-off logistical event. If outflows accelerate, the market will have already priced in the coming sales through on-chain data. The better use of this information is to cross-check with daily ETF flow reports from Bloomberg Intelligence or CoinShares rather than reacting to every wallet movement.
Ultimately, the $504.9 million transfer is a reminder that crypto ETF flows are now a core driver of Bitcoin and Ethereum price action. Tracking institutional flows, not just spot price, has become essential for any watchlist decision.
Prepared with AlphaScala research tooling and grounded in primary market data: live prices, fundamentals, SEC filings, hedge-fund holdings, and insider activity. Each story is checked against AlphaScala publishing rules before release. Educational coverage, not personalized advice.