Custody

Custody in cryptocurrency describes who technically holds and controls the private keys that authorize movement of a wallet's funds, and therefore who bears operational responsibility for keeping those assets safe.

When a third party, such as an exchange, bank, or specialized custody firm, holds the keys, the arrangement is custodial: the provider executes transactions on the client's behalf and is expected to run strict security controls, including multi-signature approval and deep cold storage for the bulk of client funds, moving only a small operational balance into a connected hot wallet for day-to-day withdrawals. Self-custody flips this: the individual generates and stores their own keys, typically in a hardware or software wallet, and no intermediary can freeze, seize, or move the funds without the owner's signature.

Institutional investors overwhelmingly rely on regulated custodians rather than self-custody. In the United States, rules require registered investment advisers to keep client crypto with a qualified custodian, a role filled by chartered banks and trust companies such as Coinbase Custody, BitGo, and Anchorage, which offer insurance, audited controls, and segregated accounts. Regulated custody became especially prominent with the rise of spot Bitcoin exchange-traded funds, whose issuers must appoint a qualified custodian to hold the underlying coins. In the European Union, MiCA imposes similar duties on licensed crypto-asset service providers: client assets must be segregated from the firm's own holdings and never used for the custodian's own account.

The trade-off is trust versus convenience. Custodial services simplify recovery, compliance, and large-scale operations but reintroduce counterparty risk, as shown by exchange collapses where custodial deposits became unrecoverable. Self-custody removes that risk but places full responsibility, and consequence for lost keys, on the user.