The most concentrated position in digital assets is not a whale wallet — it is a custody account. Roughly 84% of United States spot Bitcoin (BTC) exchange-traded fund assets sit with Coinbase, and the parent company of the New York Stock Exchange has decided that number is a business opportunity rather than a fact of life. Intercontinental Exchange (ICE) has begun pitching ICE Digital Trust to fund issuers as a second name on the prospectus, targeting a digital-asset ETF complex it sizes at about $184 billion.
The pitch works because the concentration is unusual by traditional-finance standards. In equities and fixed income, a large issuer routinely spreads custody across several qualified custodians so that one operational failure cannot gate creations and redemptions across an entire product shelf. Crypto ETFs inverted that convention on day one, and three years of asset growth hardened the exception into the norm.
The numbers behind the choke point
Data compiled by CryptoSlate as of April 8, 2026 put $77.10 billion of a $91.71 billion US spot Bitcoin ETF market with Coinbase as custodian or primary custodian — 84.1% of the total. Under a stricter methodology that strips out funds naming several custodians without disclosing allocations, the figure is $74.06 billion, or 80.8%. Either way, the concentration holds.
The issuer list explains why. BlackRock’s IBIT alone accounted for $55.70 billion of custodied assets, with Grayscale’s funds at $14.67 billion, Bitwise’s BITB at $2.67 billion and ARK’s ARKB at $2.59 billion. Greg Tusar, Vice President of Institutional Product at Coinbase, has said the company “already custodies more than 80% of the world’s crypto ETFs” — a claim the filings support rather than contradict.
Diversification has begun, but mostly on paper. BlackRock names Anchorage Digital as an alternative custodian for IBIT; ARK lists BitGo and Anchorage alongside Coinbase; Valkyrie’s BRRR names BitGo and Komainu without disclosing allocations. VanEck uses Gemini. Fidelity is the outlier, self-custodying FBTC through Fidelity Digital Assets. Naming a backup custodian in a prospectus amendment and actually moving coins to one are different acts, and the industry has done far more of the first.
What ICE is actually selling
ICE Digital Trust is a New York state-chartered, limited-purpose trust company supervised by the New York State Department of Financial Services. That charter is the whole product. It qualifies the entity as a custodian under the Investment Advisers Act of 1940, which is the specific box a registered fund’s board needs ticked. ICE acquired the custody business in May 2025 and, in a white paper published on June 1, 2026, framed it around offline storage, a multi-step authorisation chain and what it calls “robust safekeeping frameworks and capabilities”.
The competitive set is narrow. Coinbase Custody Trust, BitGo, Anchorage Digital, Fidelity Digital Assets and Gemini are effectively the entire qualified-custodian bench for US-listed funds, and BitGo reports safeguarding more than $100 billion in digital assets. What ICE brings that none of the others do is the same corporate parent that already runs NYSE listings and the ICE ETF Hub creation-redemption workflow — a bundling argument, not a security argument.
Why issuers have not moved faster
The honest reading of the last three years is that concentration persisted because it was cheap and it worked. No US spot crypto ETF has suffered a custody-driven creation or redemption failure. Coinbase’s operational record through the 2025 drawdown and this year’s grind lower — Bitcoin traded at $64,753 on August 6, 2026, per CoinGecko — has given boards no incident to point at when justifying the cost of a second integration.
That is the contrarian read on ICE’s timing: it is pitching a risk that has not yet materialised, into a market where assets are falling rather than rising. Custody fees scale with assets under management, and a shrinking ETF complex is a harder place to sell a second custodian than a growing one.
The counter-argument is structural rather than event-driven. BNY Mellon’s move to add staking to its custody stack with Galaxy running validators shows incumbents building crypto capability inside regulated perimeters, and Hong Kong’s 2026 virtual-asset dealer and custodian regime is codifying custodian separation as a licensing condition rather than a best practice. Where regulators write diversification into rules, procurement follows.
What happens next
Expect the first mandates to be small and defensive: a secondary allocation on a mid-tier fund, disclosed in a prospectus amendment rather than announced. That is how Anchorage Digital built its mandate book, and it is the only path that does not require an issuer to publicly criticise its existing custodian. The signal to watch is the custodian language in the next round of N-1A amendments from Grayscale, Bitwise and ARK — and whether any issuer discloses an actual split of assets rather than a list of permitted names. Until an allocation is disclosed, the choke point stands regardless of how many custodians appear on the cover page.
This article is informational analysis only and is not financial, investment, or trading advice. Cryptocurrencies are highly volatile and can lose substantial value rapidly. Past performance and historical patterns do not guarantee future results. Do your own research and consult a regulated financial adviser before making any investment decision.
Karthik Subramanian
Karthik Subramanian is a founder, writer, and technology consultant with nine years in the crypto ecosystem. He covers token economics, L1/L2 infrastructure, DeFi protocols, wallets/custody, and the bridge between crypto and forex—broker technology, liquidity, and macro drivers. Karthik’s writing focuses on clear, practical frameworks that help professionals evaluate new products and on-chain innovation alongside FX market realities.
