The sale of goods or property in public to the highest bidder. There are usually conditions of sale by which all bidders are bound. A bid may be withdrawn at any time before the auctioneer brings down the hammer, and the seller is likewise entitled to withdraw any lot before the hammer falls. It is illegal for the seller or anyone on their behalf to make a bid for their own goods unless their right to do so has been reserved and notified before the sale. `Rings' of dealers agreeing to keep prices down are illegal. A reserve price is kept secret, but an upset price (the minimum price fixed for the property offered) is made public before the sale. An auction where property is first offered at a high price and gradually reduced until a bid is received is known as a Dutch auction. In 1988, art auctioneers (handling not only pictures, but other items of value such as furniture) were required by a British judge's ruling to recognize the possibility of the artwork being of great value, and to carry out `proper research' on their provenance. Subject by: Russell Webb