A public auction is an auction held on behalf of a government in which the property to be auctioned is either property owned by the government, or property which is sold under the authority of a court of law or a government agency with similar authority.
Sale of property owned by the government
Government property sold at public auction may include surplus government equipment, abandoned property over which the government has asserted ownership, property which has passed to the government by escheat, government land, and intangible assets over which the government asserts authority, such as broadcast frequencies sold through a spectrum auction.
Public auctions of government property may be conducted by whichever agency is auctioning the property. Some substantial items have been sold at public auction. For example, the United States Navy cruiser USS Philadelphia (C-4) was sold at such an auction at the Puget Sound Navy Yard in 1927.
Sale of private property in a public auction
Private property may be sold in a public auction for a number of reasons. It may be seized through a governmental process to satisfy a judgment rendered by a court or agency, or to liquidate a mortgage foreclosure, tax lien, or tax sale. Usually, prices obtained at a public auction to satisfy a judgment are distressed - that is, they are much lower than the price which would be obtained for that property if the seller were free to hold out for an optimal time to sell. In the United States, public auctions to satisfy judgments are usually conducted under the authority of the sheriff of the county or city in which the property to be auctioned was seized pursuant to the judgment, and an auction held for such a purpose is also called a Sheriff's sale.
Real property may be subject to a public auction in order to partition the property between joint tenants who can not agree as to how the property should be divided. An estate sale conducted at the direction of a probate court may also be conducted as a public auction.