Descending price auction is an auction with a reduced price. Sometimes this word is used to refer to a Dutch auction, sometimes — a reverse auction, when the initiator is not the seller, but the buyer.
The buyer announces his desire to purchase a certain product and calls the starting price of the transaction. Sellers lower their prices and offer their products for less than the price of their competitors.
Descending price auction continues until there is one participant who has reduced the price more than others. If the price has dropped to zero, but there are still a few participants, the descending price auction can continue to increase the price — it will be the value that the winner will pay the buyer in addition to his product.