Quote from ammo:
timber hill was one of the forerunneers in developing the computerized option models that would take all option trades that were pennies over or under valued and hedge everything back to 0,if IB is running a few 100 million or over a billion in traders sum positions,not to mention there own positions,they would be foolish not to have a hedging dept just to minimize there risk if shit hits the fan,if they didn't,you might find it hard to close your acct and collect your cash,should a black monday event wipe out several,maybe hundreds of accounts,first options corp had one trader blow out for 50 million in 87,50 million debit on a 3 million dollar llc accct, they had to eat it