what's the best algo/way to fill missed MOO orders?

Cannot use MKT orders in premarket, it will get rejected.

 

When did you have a missed MOO? Are you sure you're not looking at the wrong opening?

 

I don't use MOO , but I'm pretty sure those are the instructions on IB website,( thanks Val)
https://www.interactivebrokers.com/en/index.php?f=598
I can see it doesn't seem logical as your entering a mkt order good till the open so you might think it will either try and fill in pre mkt or cancel on open , but those are the instructions.

 

Not sure what you mean. OPG means it's directed to the auction process at the exchange, not pre-market. OPG order would never fill in pre-market.

 

The reason why to me it's confusing is the box on IB is I believe "time in force box " including day , gtc , and opg , though thanks to your info it seems opg isn't a time in force criteria at all.

 

Technically it is a TIF criteria. It's in effect during the auction process.