Ankheroo.......I think this example given by Joltin should be pretty clear......when you put in a BUY AT THE MARKET AT CLOSE OR A SELL AT THE MARKET AT CLOSE.......the price is determined by the 4:00 PM BUY or SELL MARKET QUOTE PRICE......A MOC order is at the MARKET......

"So does this mean that at 3:30pm on a day where ARU is selling at 9.50 I can put in a buy MOC order at $9.00 and sometime before 4:00pm also put in a matching buy order bringing the stock down .50 after hours all by myself? Scary.

If that's the case watch for my $11.00 buy/sell MOC tomorrow at 4:10 LOL.

safeharbour"

Let's say the mkt. 9.45bid --9.50 offered. at 4 pm. A buy MOC order means BUY AT THE MKT.AT CLOSE which would be 9.50. If you put a price on it of $9. it is not an MOC order it is a limit order.& until the stock tanks to 9.00 your order is irrelevant.. Nothing is traded after 4pm. MOC buy orders wud only be traded at $9.50. MOC sell orders wud only sold at $9.45. Anything with a price on it is not an MOC order.

Regards

Joltin