> stock you do own, whose purchase long ago settled, is being lent out without your direct knowledge by the broker for a profit, which is like ... what? A grea

> stock you do own, whose purchase long ago settled, is being lent out without your direct knowledge by the broker for a profit, which is like ... what? A great thing that helps keeping the fees down, and understood by everyone in the industry, and (thanks to elaborate and battle tested systems) hardly ever a problem. Just like overbooking on airplanes. There are enough problems in the financial industry; this is not one of them. Next, brokerages are not allowed to use customer money as collateral, that's why they don't use "money that pretty obviously was there (had been deposited years ago)." Regarding "people like to ridicule Bitcoin": the equity markets have many orders of magnitude more transactions per day than crypto can handle.