30-11-502. Sale by auction. (1) In a sale by auction of goods by lot, each lot is the subject of a separate sale.

(2) A sale by auction is complete when the auctioneer announces the sale by the fall of the hammer or other customary manner. When a bid is made while the hammer is falling in acceptance of a prior bid, the auctioneer may reopen the bidding or declare the goods sold under the bid on which the hammer was falling.

(3) An auction sale is with reserve unless the goods are in explicit terms put up without reserve. In an auction with reserve, the auctioneer may withdraw the goods at any time until the auctioneer announces completion of the sale. In an auction without reserve, after the auctioneer calls for bids on an article or lot, that article or lot cannot be withdrawn unless a bid is not made within a reasonable time. In either case a bidder may retract a bid until the auctioneer's announcement of completion of the sale, but a bidder's retraction does not revive any previous bid.

(4) If the auctioneer knowingly receives a bid on the seller's behalf or the seller makes or procures a bid and notice has not been given that liberty for the bidding is reserved, the buyer may avoid the sale or take the goods at the price of the last good faith bid prior to the completion of the sale. This subsection does not apply to any bid at a forced sale.