I would argue it's not necessarily a problem to have liabilities for which you do not have assets on hand, whether it's Bitcoin or some security. The difference between these two situations is:
1) FTX didn't even bother listing their customer liabilities on their balance sheet, unlike Citadel.
2) I would assume (hope) that Citadel isn't a completely fraudulent company without the capital to make good on those assets if delivery is demanded!
It is the same, it's the fact that you don't really own it or know if the 3rd party has it or has the means to get it. If you have the keys to the wallet you're certain of what you have and you have full domain.
They’re a market maker, so wouldn’t those be options contracts? The “securities owned” line would be other options contracts that hedge against them, no?
Citadel Securities has in their books securities sold, not yet purchaed. $65 billion. How is this not the same thing ? lol