When the SEC greenlit spot Bitcoin ETFs in January 2024, the headlines celebrated access for everyday investors. The quieter story was structural: the approval framework required that ETF issuers use SEC-registered or state-chartered qualified custodians for actual Bitcoin holdings. That requirement didn't land on a wide-open competitive market. It landed on a list of institutions short enough to count on one hand—with COIN at the top of it.
Every dollar that flows into BlackRock's IBIT, Fidelity's FBTC, or any of the other approved spot products sits inside a custody arrangement. Coinbase Custody Trust Company holds the underlying Bitcoin for the majority of approved U.S. spot products, including IBIT, which crossed $70 billion in AUM in 2025. Custody fees are typically a fraction of a basis point on AUM—but when the base is measured in tens of billions and grows regardless of whether Bitcoin is rallying or crashing, the fee stream is durable infrastructure revenue, not a directional bet.