Quote from sprstpd:
I think you are crediting the busting process too much. In my experience, exchange discretion, in contrast to explicit busting rules, opens the process up to favoritism and abuse.
There are specific rules for busts, right? How much discretion do the exchanges really have? I have only dealt with CME (thru IB) on busts and they have been great about it.
One of my busts was when the market was 2.50 - 3.00 and I entered an order for $8 (should have been a call but I entered a put). I soon realized I didn't have the right contracts in my account and noticed I entered it wrong. At that point, before checking the confirmation, I thought the order would have just gone off at the ask and I just had to eat the spread, no problem. It actually went off at $8. The CME claimed to be dumbfounded about how that order could even execute with all those orders at $3, 3.25, 3.50 etc... and they promptly busted it.
Point being, there is something seriously wrong with the "system" when I can fat finger an order like that and someone waaaayyyyy back in the line can get filled ahead of all the others. A bust is the only way to rectify that. If I had been filled at $3, I wouldn't have called and asked for the bust. Paying the spread would have been the cost of my mistake and I would have happily paid it.
IB's only role is to call the exchange and ask for it on my behalf, which they did. IB doesn't want to have to take the time to deal with all the admin crap that goes with a bust. No broker wants that headache.