An English auction is an open-outcry ascending dynamic auction. It proceeds as follows.
The auctioneer opens the auction by announcing a suggested opening bid, a starting price or reserve for the item on sale.
Then, the auctioneer accepts increasingly higher bids from the floor, consisting of buyers with an interest in the item. The auctioneer usually determines the minimum increment of bids, often raising it when bidding goes high.
The highest bidder at any given moment is considered to have the standing bid, which can only be displaced by a higher bid from a competing buyer.
If no competing bidder challenges the standing bid within a given time frame, the standing bid becomes the winner, and the item is sold to the highest bidder at a price equal to their bid.
If no bidder accepts the starting price, the auctioneer either begins to lower the starting price in increments, bidders are allowed to bid prices lower than the starting price, or the item is not sold at all, according to the wishes of the seller or protocols of the auction house
Unlike sealed-bid auctions, an English auction is "open" or fully transparent, as the identity of all bidders is disclosed to each other during the auction. More generally, an auction mechanism is considered "English" if it involves an iterative process of adjusting the price in a direction that is unfavorable to the bidders. In contrast, a Dutch auction would adjust the price in a direction that favored the bidders. When the auction involves a single item for sale and each participant has as an independent private value for the item auctioned, the expected payment and expected revenues of an English auction is theoretically equivalent to that of the Vickrey auction, and both mechanisms have weakly dominant strategies. Both the Vickrey and English auction, although very different procedurally, award the item to the bidder with the highest value at a price equal to the value of the second highest bidder.
Variations
There are many variations on this auction system. Sometimes, the reserve price is not revealed. Also, bids may be made with instead of being called out. Such signals can include tugging an ear or raising a bidding paddle. Another variation on the English auction is the open-exit auction, where the bidders must announce that they are dropping out of the bidding and they can't reenter. In France, when the last bid has been made in an auction for an art object, a member of the state can say "Préemption de l'état" and buy the object for the highest bid. Some housing cooperatives similarly allow members of the cooperative to pre-empt any buyer of a house constructed by the cooperative. English auctions may end at a specified time, or when no new bids have been made after a period of time.
Swedish auction
A less regulated auction where the bidders are not bound by their bids, and the seller is free to accept or decline any bid made is sometimes called a Swedish auction, a term originally made up by an English journalist writing about the Swedish real estate market. In August 2017, several Swedish housing brokersasked the law to change, so as to make the bidding binding.
Candle auction
A candle auction is a variation in which the end of the auction is signaled by the expiration of a candle flame. This was intended to ensure that no one could know exactly when the auction would end and make a last-second bid.
A Japanese auction is a variant in which the current price changes continuously according to the auctioneer's clock, rather than by bidders' outcries. Bidders can only decide if and when to exit the arena. At first glance, this seems equivalent to English auction: apparently, in an English auction, it is a dominant strategy for each buyer whose price is above the displayed price, to always bid the minimal allowed increment above the displayed price, so the price should increase continuously. However, in real-life English auctions, jump bidding is often observed: buyers increase the displayed price much more than the minimal allowed increment. Obviously, jump-bidding is not possible in a Japanese auction. This may be seen as either an advantage or a disadvantage of the English auction format.
Selling more than one item
The English auction has variants for selling multiple identical items or multiple different items.
