Originally posted by Thug_Life
<i>An example of such manipulation might work like this: if August 12 calls for options on XYZ Co. were quoted at 10 cents bid/20 cents offered on the PCX, the customer might enter an order to buy one options contract at 19 cents on the PCX, typically also raising the best bid at other exchanges to 19 cents.
The customer then would enter an electronic order to sell 50 contracts, hitting the bid at 19 at another exchange such as the CBOE. That market maker must fill the order at the best bid of 19 cents, making himself long 50 contracts at 19 cents.
After the 50-lot is sold at the inflated price, the market usually reverts to its original 10 bid/20 offered spread. Theoretically, that means the customer made 9 cents or a total of $450 on the trade, since each options contract represents 100 shares of stock and the order involved 50 contracts. And the market maker lost $450 because the best he can do is offset his position at 10 cents in options or an equivalent in a stock hedge.</i>
It sounds a lot more like a flaw of the system. They would do better to modify the system than punish the traders for taking advantage of their flaw, imo.