Exchange & Custody Risk

Exchange and custody risk is the danger that the entity holding your crypto on your behalf fails to return it. Funds on a centralized exchange are a liability of that exchange: you have an IOU, and security breaches, insolvency, fraud, mismanagement, withdrawal freezes, or regulatory seizure can impair or erase your claim — history includes large exchanges that lost customer assets or collapsed entirely. The phrase "not your keys, not your coins" means that without control of the private keys you do not truly hold the asset. Self-custody removes counterparty risk but transfers responsibility entirely to you: lost keys or seed phrases, or a signed malicious transaction, are typically irreversible, so the real task is choosing where the risk you can best manage lives.

In plain English — When your crypto sits on an exchange or with a custodian, you hold a claim against that company — not the coins themselves. If it is hacked, becomes insolvent, freezes withdrawals, or commingles funds, you can lose access or lose everything, as several high-profile failures have shown. "Not your keys, not your coins" captures the core idea: only assets in a wallet whose private keys you control are truly yours. Self-custody, in turn, shifts the risk to you — lost keys mean lost coins with no recovery.

Traders left funds on a major exchange that suddenly halted withdrawals and later collapsed; many became unsecured creditors and recovered little or nothing for years. The price could have been "up", but their balance was frozen and gone.