Coinbase Custody is responsible for managing approximately 84% of U.S. spot Bitcoin ETF assets, amounting to around $77 billion, according to Marc Baumann, founder of research firm fiftyonexyz. This concentration of funds with a single custodian has sparked discussions about potential systemic risks and regulatory scrutiny, especially as Bitcoin prices rise to about $77,000 and Coinbase receives conditional approval for a national trust bank charter from the OCC.