The swaps are the lending instrument. He used CFDs which are a type of OTC derivative. Instead of buying the stock, you put up some margin and (usually) promis

The swaps are the lending instrument. He used CFDs which are a type of OTC derivative. Instead of buying the stock, you put up some margin and (usually) promise to swap cash daily based on the movement in an underlying stock (or basket of stocks) i.e. instead of buying F, you promise to pay/receive the loss/gain in F stock every day. The leverage comes, of course, when investment banks say you can pay/receive the cash flows on a position worth X shares but only need to put margin that is significantly less than the actual purchase price for X shares i.e. for a $100 notional exposure, you only need to put up $5 in margin. Something to bear in mind if this sounds confusing. The risk doesn't go anywhere. If an investment bank agrees to pay the gain in the share price of AMZN, they hedge their risk by buying shares. There are a few unique things about the case, it seems implausible that Archegos weren't aware they were cornering the market for certain stocks through investment banks hedging their exposure, but the macro point is that the risk hasn't disappeared. Amazingly, this happened in 2007 too (everyone thought that the MBS market was deep and liquid...no, it was pretty much all owned by some particularly dense bankers in Germany/Japan/etc.). People forget that risk doesn't go anywhere and there is a point where risk-taking is just too high relative to the actual productivity of the underlying assets. Also, I don't the detail is out there. But the $20bn, I believe, refers to the gross leveraged position. It is very likely that he was leveraging every bit of equity he had on the way up (it doesn't matter anyway, all of his equity is going to be wiped out).