BlackRock-linked wallets sent about $270 million in Bitcoin and Ethereum to Coinbase Prime, according to the on-chain transfer screenshots from Lookonchain and Arkham. The transfers add up to 2,019 BTC valued at around $181.7 million and 29,928 ETH worth about $91.3 million. Instead of one big package, the activity looks split across a bunch of deposits, which is a typical pattern for how institutions handle and execute things.

On the Ethereum side, Arkham’s transfer view shows three big blocks — 10,000 ETH, 9,928 ETH and another 10,000 ETH — sent from wallets linked to BlackRock’s ETHA Ethereum ETF infrastructure into a Coinbase Prime deposit address. On the Bitcoin side, the same view shows repeated 300 BTC deposits plus a 219.392 BTC entry, linked to wallets tagged to BlackRock’s IBIT Bitcoin ETF.

Coinbase Prime is designed for institutions, offering custody, OTC-style execution and exchange access all in one place. When you put money into Prime, it is not like a public trade confirmation. But it puts your assets where they can be sold, used as collateral for derivatives or used to settle ETF creation and redemption activity.

Bigger picture

The transfer lines up with a softer ETF flow print, as visible in SoSoValue data. The U.S. Bitcoin spot ETF table shows a daily net outflow of $158.25 million for last Friday, with IBIT reporting the largest single-fund outflow at $173.58 million.

The weekly view, as of Dec. 19, 2025, shows a weekly net outflow of $497.05 million. However, cumulative net inflows remain above $57.41 billion, and total net assets are close to $114.87 billion.

The TradingView snapshot shows BTC at around $90,298 after an intraday run from the high-$87,000s. With flows negative and Prime deposits rising, the market will treat each new tranche as sell-side supply until proven otherwise.