Market prices aren't continuous, so you cannot guarantee that you can close the customers position at the point where they are wiped out. So a cryptocurrency casino that offers margin to users cannot guarantee that they won't just suddenly be insolvent.
They also accepted magic beans as collateral no just their own FTT but all manner of other dogshit where there couldn't be a realistic realtime market price.
The key point is that these bucketshops end up as the counterparty to their customers trades the net result was that FTX itself was essentially long all manner of illiquid scamcoins and massively short Bitcoin.
This complicates accounting for the total loss-- if you deposit $1000 but then turn it into $100k worth of "bitcoin" using trades with 100x leverage-- though the bitcoin never existed it was just an entry on FTX's books-- and then FTX implodes what the amount lost? Arguably closer to $1000, but right now the figures about FTX all use the highest number. But the customer didn't actually lose that full amount-- it was just a fantasy.
A lot of the dialog about the fraud at FTX centers on diverting company assets for personal/family use-- which indeed doesn't appear to be good, but so far that doesn't appear to have happened at a scale that they couldn't have operated out of if not for the fact that the entire business itself-- basically selling people paper assets which weren't even backed by meaningful collateral-- was fraudulent.
And this is an important distinction because it changes what risk people should be looking for... The 'crypto' ecosystem is highly volitile at best-- full of garbage that is sure to fail. Business offerings that aren't provably implosion proof will almost all eventually implode.
Compare to your typical US retail brokerage-- margin is available, but 2x leverage at the absolute most, highly controlled, regulated, and risk managed, riskier assets either can't be used as collateral or count far less. The assets and customers are diversified (and when they become less so, leverage is further reduced), and there is industry provided insurance mechanisms to backstop. In the crypto space things are massively more correlated, unregulated, customer are all over the world so there is seldom any recourse against them, no one has every (AFAIK) gotten in trouble for manipulating a cryptocurrency market, and instead of 2x leverage _20x_ is common at these casino services (and 20x isn't even the limit).
Is it normal for margin loan funds to come from customer deposits? For example, if I deposit on Charles Schwab, is the cash held in my Schwab account used as capital for margin loans to other Schwab customers? I would think not (unless I'm misunderstanding how finance works). Like of course the money is probably lent out like banks do, but FDIC insured banks have rules about what types of things they can lend money to, right?
I would think that using customer deposits to make margin loans to other customers would be fraud even if Alameda wasn't in the picture. That's what I fundamentally don't understand about SBF's mumbo jumbo; how would Alameda (or any other customer) take a margin loan out of customer funds if customer funds are supposed to be segregated from FTX company funds? Isn't the admission that a margin loan to Alameda led to the loss of customer funds an admission that depositors were defrauded?
Traditionally, lending deposits out as loans (especially mortgages) was seen as the most important thing that banks did, their core function. Nowadays things are more abstract and regulations are different, but it wouldn't surprise me if margin loans could still be at least partly funded (at least in an abstract capital-ratio sense) from deposits.
[0] https://www.finra.org/rules-guidance/rulebooks/finra-rules/3...
Brokers and exchanges are obligated to park customers' money in an escrow, and may even be required to insure them [1] for a good measure. Under no circumstance are customers' funds lent out. So where do they get money from to lend? Brokers lend either their own money or get into arrangements with liquidity providers. These are big institutions/hedge-funds etc., who offer to lend money in exchange for attractive returns. They get into a different agreements and are fully aware of risks they are taking on.
This all was a big problem I. The us up through Great Depression, and then the securities exchange act of 1934 was implement to regulate these practices quite successfully over the years.
So they took a margin loan using all their FTT as collateral, then lost all the money. Normally you wouldn't be able to lose more than you've left as collateral, but they weren't like other customers (see above). But there's also the fact that the collateral was semi-BS, so FTX can't sell it to get the money back anyway. FTX printed the FTT out of thin air and then sent it to Alameda (surely for some purported reason). Alameda then used this semi-fake collateral to loot all FTX's customer deposits. (It was fake in the sense that you can't sell all of it at the mark-to-market/last-match price). You can see how FTX is involved at every step of the way here, and is at the root of the scheme, not merely a criminally negligent player.
But honestly it just keeps going deeper and deeper, as it sounds a lot like funds were missing prior to any of this happening, and that even if they could pay all this money back, there wouldn't be enough money, and that the margin loan wasn't just used for investing but also frivolous spending. Don't try to make sense of SBF's actions, they don't make much sense (Why go on a shopping spree that worsen's your already-insolvent exchange? Why tie up withdraw-at-anytime depositor's funds into 10-year-time-horizon VC funds? IDK, why talk so much publicly against your lawyer's wishes and your own best interest?)