New York Laws
Part 3 - General Obligation and Construction of Contract
2-328 - Sale by Auction.

(1) In a sale by auction if goods are put up in lots each lot is the
subject of a separate sale.
(2) A sale by auction is complete when the auctioneer so announces by
the fall of the hammer or in other customary manner. Where a bid is made
while the hammer is falling in acceptance of a prior bid the auctioneer
may in his discretion reopen the bidding or declare the goods sold under
the bid on which the hammer was falling.
(3) Such a 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 he 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on an article or lot, that article or lot cannot be withdrawn unless no
bid is made within a reasonable time. In either case a bidder may
retract his 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 such a bid, and notice has not been
given that liberty for such bidding is reserved, the buyer may at his
option 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 shall not
apply to any bid at a forced sale.

Structure New York Laws