So this seems like a pretty easy way to stop a stock - change the collateral requirements.

From what I heard from the WeBull CEO, what you described sounds right. And he said the whole market could not function.

So in order for other stocks to trade (which have much lower requirements) they had to shut down several stocks.

So I'm sure the big shorts would know that if they get super screwed (price going higher and higher) this collateral requirement would cause this (and the stock to drop big like it did to $112 the other day)?

And this is basically all because of the risk that some hedge fund may not be able to pay (which causes collateral requirements to change)? Seems like the rules should change for these big shorts.