Wallets labeled as related to BlackRock’s ETF transferred 3,580 BTC, valued at approximately $226.8 million, to Coinbase Prime on June 8, 2026, drawing renewed attention to the fund flows of the iShares Bitcoin Trust ETF amid a series of consecutive outflows recently recorded by IBIT.
On-chain data shows 3,580 BTC transferred to Coinbase Prime, the execution and settlement infrastructure used by BlackRock for IBIT operations, while the fund’s custody is managed by Coinbase Custody. This transaction is notable amid rising ETF outflows, but it is insufficient to conclude that this Bitcoin has been sold into the market.
What Happened
On-chain data on Arkham shows a cluster of wallets labeled as related to BlackRock transferred 3,580 BTC, valued at approximately $226.8 million, to Coinbase Prime on June 8, 2026. The transactions were split into multiple batches, highlighted by a series of repeated 300 BTC transfers, each worth around $19.02 million.
The largest transaction during this period was a transfer of 3.3K BTC, valued at approximately $209.23 million, from a wallet labeled BlackRock: Coinbase Prime to the Coinbase Prime Hot Wallet. Arkham also recorded an additional 15,095 ETH, valued at approximately $25.17 million, transferred within the same timeframe.
BlackRock moves $226M Bitcoin to Coinbase Prime. Source: TradingView
BTC flows into Coinbase Prime are often monitored by traders because deposits into exchange infrastructure can signal that liquidity is being prepared for use. However, current data only confirms that assets moved between wallets tagged by Arkham. To date, BlackRock has made no separate move regarding these transactions.
Why Coinbase Prime Matters
Coinbase Prime is an institutional-grade infrastructure, not just a regular spot exchange deposit address. According to filings from the iShares Bitcoin Trust ETF, BlackRock names Coinbase Custody Trust Company as the Bitcoin Custodian, and Coinbase Inc. as the Prime Execution Agent, supporting Bitcoin buying, selling, and transaction processing operations related to the fund.
This makes the transfer of 3,580 BTC to Coinbase Prime viewable as part of ETF operational activities. For IBIT, assets may be moved through Prime for execution, settlement, or handling creation/redemption, rather than simply reflecting an immediate market sell order.
Therefore, while on-chain data confirms the assets moved, it does not yet indicate whether this amount of BTC will be sold, held within the Prime infrastructure, or used for ETF processing.
ETF Flow Context
Outflow pressure in the first week of June appeared not only in IBIT but spread across the spot Bitcoin ETF cohort in the US. According to Farside Investors, the entire group recorded approximately $1.72 billion in net outflows during the trading week ending June 5, 2026, though cumulative flows remained at around $53.99 billion in net inflows.
IBIT accounted for the majority of this record outflow streak. The fund recorded approximately $1.34 billion in net outflows during the same week, with the largest single-session outflow being $440.3 million on June 1. As of June 8, 2026, IBIT still led the US spot Bitcoin ETF cohort in terms of cumulative flows, with approximately $62.47 billion in net inflows since launch.
Daily BTC ETF flows. Source: Farside Investors
The fact that IBIT accounted for the majority of last week’s outflow pressure has led the market to monitor wallet movements related to this fund more closely, especially when the destination is Coinbase Prime.
What To Watch
The move to transfer 3,580 BTC to Coinbase Prime by BlackRock quickly generated mixed opinions within the crypto community. Some traders view this as a potential selling pressure signal, while others argue it could just be an operational activity related to the ETF.
In subsequent sessions, the data to watch includes IBIT’s daily flows, total flows of the US spot Bitcoin ETF cohort, and further movements from Coinbase Prime. If IBIT continues to record large outflows while BTC leaves Prime wallets for other liquidity addresses, concerns over selling pressure could rise. Conversely, if the BTC remains within the Coinbase Prime infrastructure and IBIT’s flows stabilize again, the June 8, 2026 transaction is highly likely part of ETF operational activities.
