Eddy,

1. What each seller actually did can only be answered by the sellers. However, is very likely each individual seller placed the three-digit orders, because KRY is under AMEX/NYSE.

2. Only two decimal points??? Seems we have come a long way from 1/8 of a dollar. Anyway, SP goes all the way out to four places for some of the Big Guys who move a lot of shares. Although, when under a buck, SP typically may be available to four decimal places for retail traders.

3. Just guessing on this one... It sounds as though your account is not completely commission free, or has some sort of surcharge, possibly for trades over a certain order size. There are many low/free commission outfits, but they seem to limit order size unless you pay extra.

In addition, my understanding is that Market Makers do only Nasdaq stocks. The Market Maker takes a position (long, short, both) and turns a profit/loss at the end of each day by "flipping" stock.

For NYSE/AMEX stocks they are called Specialists. A Specialist is an intermediary providing liquidity.