Quote from GTC:
NoWorries, Do you mean Zecco offers Market-At-Open order type? What type of equity orders do they offer? How is their financial transaction? I heard they withhold taxes on sale orders for some people unless you submit W-9 or so long in advance. Do they withhold taxes for you?
They only offer Market, Limit, Stop, and Stop Limit orders. I don't need market-on-open orders as NYSE market orders submitted prior to the open are supposed to fill at the open, due to the auction process. Zecco routes all orders through Penson. I have never filled out a W-9 and they do not withhold taxes for me.