A public auction is a procedure for the sale of a good through which the buyer and the price are intended to be determined, according to the system of competition between several possible buyers, awarding the good to the one that offers the highest price. Furthermore, the public auction differs from other types of auctions by the fact that anyone can bid to purchase the good.

The term public auction is often also related to the judicial auction that is carried out, on a compulsory basis, for the sale of one or more assets of a debtor that have been seized for payment to his creditors.

Public auctions can be forced or voluntary.

Auctions in which the subject freely decides to sell a good, and decides that the way to maximize the sale price is to submit it to the public auction procedure, are voluntary. This procedure is commonly used, for example, in the sales of works of art.

Auctions of assets seized from a debtor are obligatory. In that case, the law usually requires the public auction procedure to provide greater transparency to the sale, and allow the price to be received by the debtor in exchange for the good to be as high as possible.

In the case of a public auction for debts, the sale price of the goods is used to pay the creditors and, if there is a remainder, it remains the property of the debtor. It is also usually necessary in their procedures to comply with a series of formalities imposed by law to give more transparency to the auction and prevent its results from being manipulated. Typical requirements in these cases are the publicity of the auction and compliance with deadlines.