MMs are not required to have stocks in their inventory to sell them, this is where all the hysteria about massive naked shorting comes from, even though it's a matter of practicality not an open window for MMs to profit from (or risk)
if i sell 100 shares and NITE buys it, then NITE sells it to you from your ameritrade account...nite's involvement is done, electronically the stock is in your account and physically its up to the TA to settle with the certs...the problem is TA's not settling on time, or being unable to trace the path in these stocks that get flipped over and over again
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