[avereveard]

but they blocked stock purchases alongside options, which makes no sense if the justification was collaterals for options

[w23j]

Stock purchases are settled after 2 days. If the buyer goes broke before that, the seller would be left holding to bag. To mitigate this risk you need to post collateral.

[avereveard]

of course, but if you buy without margin the balance in your account should already be enough to cover the collateral.

[gruez]

But it's not the brokerage's money on the line, it's DTCC's. From the perspective of the DTCC, there's no difference between a retail brokerage buying $10M of GME and lehman brothers buying $10M of GME.

[ric2b]

But if the brokerage already has your money they can use it to post collateral. And yet they banned everyone from buying. A lot of stuff doesn't add up here.