400.2-328. (1) In a sale by auction if goods are put up inlots each lot is the subject of a separate sale.
(2) A sale by auction is complete when the auctioneer soannounces by the fall of the hammer or in other customary manner.Where a bid is made while the hammer is falling in acceptance ofa prior bid the auctioneer may in his discretion reopen thebidding or declare the goods sold under the bid on which thehammer was falling.
(3) Such a sale is with reserve unless the goods are inexplicit terms put up without reserve. In an auction withreserve the auctioneer may withdraw the goods at any time untilhe announces completion of the sale. In an auction withoutreserve, after the auctioneer calls for bids on an article orlot, that article or lot cannot be withdrawn unless no bid ismade within a reasonable time. In either case a bidder mayretract his bid until the auctioneer's announcement of completionof the sale, but a bidder's retraction does not revive anyprevious bid.
(4) If the auctioneer knowingly receives a bid on theseller's behalf or the seller makes or procures such a bid, andnotice has not been given that liberty for such bidding isreserved, the buyer may at his option avoid the sale or take thegoods at the price of the last good faith bid prior to thecompletion of the sale. This subsection shall not apply to anybid at a forced sale.
(L. 1963 p. 503 ยง 2-328)