Hi All, Great forums. First post. I've done some research but I can't find a lot written about the market Opening/Closing auctions. I've read the rules for the ARCA auction and understand fundamentally what happens. What I don't understand is why the auction happens in the first place and why I would want to use the auction to get into and out of a position. If I make money I make money on the closing auction. Who is loosing money? Sorry if this is a noob question... but... well... I'm a noob. Chris