Civil Code, Art. 1476

In the case of a sale by auction: (1) Where goods are put up for sale by auction in lots, each lot is the subject of a separate contract of sale. (2) A sale by auction is perfected when the auctioneer announces its perfection by the fall of the hammer, or in other customary manner. Until such announcement is made, any bidder may retract his bid; and the auctioneer may withdraw the goods from the sale unless the auction has been announced to be without reserve. (3) A right to bid may be reserved expressly by or on behalf of the seller, unless otherwise provided by law or by stipulation. (4) Where notice has not been given that a sale by auction is subject to a right to bid on behalf of the seller, it shall not be lawful for the seller to bid himself or to employ or induce any person to bid at such sale on his behalf or for the auctioneer, to employ or induce any person to bid at such sale on behalf of the seller or knowingly to take any bid from the seller or any person employed by him. Any sale contravening this rule may be treated as fraudulent by the buyer. (n)