The component of this that the general public doesn't yet understand is that exchanges obligate market-makers to post continuous, two-sided quotations. That put

The component of this that the general public doesn't yet understand is that exchanges obligate market-makers to post continuous, two-sided quotations. That puts them in a position where they are pressured to offer stock even when they have no inventory (ie, sell short). And if that happens when there's no available borrow in the market, it's permitted because of a loophole in the regulations; market-makers can sell short even when they cannot locate the shares that they are selling. Citadel Securities is a market-maker. Presumably, they were lifted short by all the buying from Robinhood. It'd be very interesting to know how much GME stock their firm failed to deliver every day. My big worry is that the long holders think they own the stock after T+2, and possibly even start loaning the shares that haven't yet been delivered. This would falsely create borrow in the stock loan market. And if a market-maker can sell short when there's no borrowable inventory to sell, it can maliciously depress the price without ostensibly violating the law.