Proxy bidding only applies to Product Auctions.

When you place a bid for an item, enter the maximum amount you are willing to pay for that item. This amount will always be kept in secret. Whenever someone else places a bid, our service will automatically enter the lowest possible bid for you, up to your maximum proxy bid amount, until you are the winning bidder. At the end of an auction, if you are the highest bidder, you are the winner. As the winner of the auction, you only pay the lowest possible winning bid, not necessarily your maximum bid.