I thought this sort of thing has been known, or at least suspected, for some time? I mean particularly the electronic front-running and slow-market arbitrage. I never heard of rebate arbitrage.
There's a reason traders were seeking faster trading times. Again, I thought the push for faster trading times had been in the news before.
But these guys did a good job catching up to those who had already figured this out and were gaming the system.
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It seems to me that the stock market only went 'retail' in the early 80's. I was studying finance & accounting in college until '82 and while I was in college Wall Street brokerage firms could be purchased for as little as $100K. That's how little demand there was.
But beginning in the early 80's companies began shifting from traditional (DBP) pension plans to 401K's etc (DCP). Also IRA's started taking off:
http://www.ici.org/pdf/per11-01.pdf
This brought a ton of (new) individuals into the stock market.
I guess my point here is that by the end of the 80's the little guy was already getting screwed. It was just a different methodology. They allowed trades to be executed not on time of order, but prioritized by size. If the market moved one way or the other, the little guy got screwed. E.g., I had a client who had +$1 mill in the market and moved to sell on Black Monday in '87. His sell order was pushed out of the way by larger orders and by the time it was executed he had lost about 90% of his money. To rub salt in the wound, he executed a buy order when the market was at bottom. Well that order also got pushed aside by the larger ones and ended up getting executed after the market topped out that day.
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No system is perfectly fool proof (or cheat proof) and I'm sure the next gaming methodology is already being figured out somewhere by somebody.
Fern