Guy Trading at Home Caused the Flash Crash


I have always been impressed and puzzled that low-tech spoofers have much success ripping off whomever they rip off. It’s such a minimal fraud; it’s just saying that you want to sell when you don’t want to sell. It’s always surprising that that could have a major effect on markets. John Arnold has argued here at Bloomberg View that spoofing only hurts front-running high-frequency traders, while others point out that “algorithmic trading tools are used by a wide class of traders,” including long-term investors like Waddell & Reed who use algorithms to try to avoid the front-running HFTs. But the FBI’s and CFTC’s theory here is far more troubling: It suggests that existing algorithms are not just dumb enough to give spoofers some of their money, but dumb enough to give spoofers so much of their money that they destabilize the financial markets. It’s not especially confidence-inspiring to read that a guy with a spreadsheet can trick everyone into thinking that the market is crashing, and thereby cause the market to crash.

I’m not sure exactly what happened but as Bloomberg points out, even if we believe the report, it is pretty worrying that “one guy” could cause so much damage.  Makes you wonder how such a big market can be rigged, eh?