Quote from WinstonTJ:
Are you suggesting changing limit orders over to market orders? Also, are you suggesting that market orders fill sooner than marketable limit orders?
Harris explains the operating rules for markets in detail.
I spoke in generalities for using an ATS to make money.
Personally, I use market orders and if the capacity of the market at a given time is less than 5 times the capacity at the time of my entry, then I put in partial fill orders. That is a break my trade into pieces which in teurn eat up the orders showing on data menus.
If a person reates a sucessful ATS, then he has to deal with the trading platform (dashboard adjustments) to use the ATS interactively with the market's operation.
Transactions in markets usually involve a market order on one side or the other. This shows up on a OTR chart as you see the color of the bar switch to bid or switch to offer. Often there are pairs of OTR bars with one common price. Here three separate tick values are in play.
In trading, order adds and deletes ALWAYS EXCEED the transactions in the market. An ATS, to be most fficient, needs to be able to "fast track" trade to circumvent "standing in line" at a given value level. Market orders go to the head of any value level.
The OP is planning to have an ATS. Since he is working on its "participating" in the market, he has to decide on its ability to either add and dlete orders OR do transactions at the better event when the event arrives. The type of order facilites each of these separate types of goals. (Goggle "games played on the DOM").
For my ATS's, my goal is to "execute" to take the full offer of the market segment by segment. In other words, I extract capital all the time during RTH. I am not competing for scarce money; all I do is take the market's full offer.
I read Harris to understand how markets handle different types of orders. I manage to get at the front of the line at the correct event.