Bank runs are bad when there isn't a full reserve. Coinbase says it has 100% reserves.

Bank runs are how fraudulent exchanges are caught: Bitcoin is self-auditing, and either you have it or you don't, there aren't IOUs or paper receipts.

Fractional reserve banking is a prisoner's dilemma, we all marginally benefit from the status quo of credit/debit/interest, but in a crisis, the first people to pull out win, and everyone else loses.

What if Coinbase is the one buying large amounts of bitcoin? Then using reserves so they can buy/sell on both sides. See where it gets risky?

I wonder how quickly CoinBase could release funds from cold wallet(s)? Could be hours... which could pretty bad.

Right, "only 8%" is rather a lot.

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