Fund managers shaping BlackRock’s IBIT after $15 billion AUM milestone

The massive AUM reversal

BlackRock’s IBIT holds $60.62 billion in assets. Grayscale’s GBTC holds only $9.90 billion. This massive shift followed the launch of spot Bitcoin ETFs in January 2024. IBIT keeps a 0.25% expense ratio. GBTC carries a 1.50% fee. I find the 1.25% difference between these products insulting.

Investors prefer lower costs.

IBIT pulls in massive inflows. Since the start of the year, IBIT has reported about $16.6 billion in inflows. In contrast, GBTC has seen roughly $17.9 billion in net outflows since January 11. This disparity exists because GBTC is much more expensive than products like IBIT. At the end of May, IBIT assets stood at $19.5 billion while GBTC assets were $19.385 billion. IBIT also reached $15 billion in assets on March 12. On that same day, IBIT witnessed its largest daily inflow of $849 million. This helped push net inflows for all U.S. spot Bitcoin ETFs to a record of more than $1 billion. Bitcoin prices hit $73,710 earlier in the week. IBIT also leads in trading volume. On a recent Tuesday, IBIT generated $4 billion in trading, which was double the volume of GBTC’s $1.8 billion. Bitcoin remains volatile.

Leadership and custody

Samara Cohen is the Senior Managing Director and Global Head of Market Development at BlackRock. She helps shape market structure and product innovation. Previously, she led the teams for ETF and Index Investments. Her role involves managing portfolios across 65 countries and 85 markets. She rejoined in 2015. She earned an MBA from Harvard Business School and holds a BS in Economics from Wharton.

She uses Coinbase and Anchorage Digital Bank.

You already know most providers rely on Coinbase. IBIT avoids the concentration risk found in other funds by using a multi-custodian model. This setup uses both Coinbase and Anchorage Digital Bank to hold the assets. Does the multi-custodian approach actually lower risk? Samara Cohen is a member of the Global Executive Committee. She also leads the Global Diversity Steering Committee. She serves on the Board of the BlackRock Foundation and the Securities Industry Financial Markets Association.

The invisible cost

The 0.25% fee does not arrive as an invoice. The fund sells tiny fractions of its Bitcoin holdings every day to pay for operations. This process reduces the amount of Bitcoin backing each share. For 1,000 IBIT shares bought today, the holding represents 0.5662 BTC.

The drag is real.

The fee is constant.

As of late January 2026, the ratio for IBIT was 0.0005662 BTC per share. This ratio will drop as the fund sells more Bitcoin to cover expenses. While the 0.25% fee seems small, the constant selling of Bitcoin assets to cover operating expenses means that each share represents a slightly smaller amount of the underlying cryptocurrency over time. I would skip GBTC because the fee is too high. IBIT has accumulated $62.88 billion in cumulative net inflows since its launch. Over five years, a 1,000-share position in IBIT loses roughly 0.0070 BTC to fees, whereas GBTC loses 0.0412 BTC. The 0.25% fee is low compared to the 0.50% average equity ETF fee. This cost is part of the price for regulated custody. The gap between the ETF total return and the dollar-weighted return remains wide for late investors. Morgan Stanley’s MSBT has a 0.14% fee.