BlackRock buys $1B of Bitcoin over past 20 days as Grayscale bleeds another $255M

BlackRock’s iShares Bitcoin Trust (IBIT) has accumulated roughly $1.08 billion in net inflows over the past 20 days, according to on-chain data from Arkham Intelligence. During the same window, Grayscale’s Bitcoin Trust (GBTC) shed approximately $254.7 million in outflows.

The numbers behind the split

IBIT’s 20-day haul was punctuated by some standout sessions. Daily inflows hit $454 million on September 3, the kind of single-day figure that most ETFs never see across their entire lifetimes. Another notable session on August 27 brought in $277.6 million as markets rebounded from a choppy August.

Those inflows have pushed IBIT’s total holdings to approximately 785,000 BTC, with assets under management now exceeding $60 billion.

GBTC, meanwhile, sits at roughly 130,000 BTC with an AUM hovering near $10 billion.

The fee differential tells much of the story. IBIT charges 0.25% annually. GBTC charges 1.5%. On a $10 million position, that’s the difference between paying $25,000 and $150,000 per year for essentially the same exposure to the same asset.

A broader ETF ecosystem in motion

US spot Bitcoin ETFs collectively now hold over 1.28 million BTC, representing roughly 6% of Bitcoin’s total supply. The broader ETF category pulled in over $3 billion during the recent surge, with IBIT capturing the lion’s share. Bitcoin’s price has oscillated between $60,000 and $80,000 during this period.

BlackRock’s dominance in the spot Bitcoin ETF market mirrors what it does in traditional finance. The firm manages roughly $10 trillion in total assets globally, and its distribution network gives IBIT access to financial advisors, wealth managers, and institutional allocators that smaller competitors simply cannot reach.

Grayscale’s problem isn’t that GBTC is a bad product. It’s that the competitive landscape shifted dramatically when the SEC approved spot Bitcoin ETFs in January 2024. GBTC was originally structured as a closed-end trust, converting to an ETF format only after regulators opened the floodgates. By then, BlackRock, Fidelity, and others had already launched with lower fees and fresher marketing.

Grayscale has attempted to address the fee gap with its Bitcoin Mini Trust (BTC), which carries a lower expense ratio. But the migration damage to the flagship GBTC product appears to be ongoing, with outflows persisting throughout 2026 even as the broader market recovered.

What this means for Bitcoin markets

With US spot ETFs collectively holding 6% of all Bitcoin ever mined, and that percentage climbing, the supply dynamics are tilting in a direction that historically correlates with price appreciation.

At 1.5% annually, GBTC’s fee is six times higher than IBIT’s. Unless Grayscale cuts its fee substantially, the outflow trend shows no signs of reversing. Every dollar that leaves GBTC and enters IBIT is roughly net-neutral for Bitcoin’s price, but the AUM transfer reshapes which firms control the narrative around institutional crypto adoption.

Disclosure: This article was edited by Editorial Team. For more information on how we create and review content, see our Editorial Policy.