In this digital paper trail market every transaction can be reviewed, there are two ends to each transaction and there is a record of it. That's how they undid some of the trades in the May flash-crash and that's how they take a snapshot in time to determine who holds what. The naked shorting gets to a point of straddling criminal activity and they have many tricks to masque their methods to profit without the downside risk. They are now facing their downside risk.
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