on 09-25-2012 03:10 PM
Just as you can place a bid for your maximum amount, so can everyone else. When a bid is entered, it is compared to the leader's maximum bid and whichever is higher takes the lead at no more than one bid increment above the second highest bid. When there are 2 high max bids compared, this can make the current price jump significantly.
The only time that the bid goes up incrementally is when at least one bidder is placing the MINIMUM bid.