In trading, the term at or better denotes an instruction given to a broker to buy or sell an asset if and when its price reaches or exceeds a predefined rate, or falls to or below a predefined rate.
The term is often used synonymously with the term limit order. However, limit orders may be strict (a specific price at which a security should be bought or sold) or they may be limit-or-better (identical to at-or-better orders). The way in which these terms are used varies between brokers and exchanges.
At-or-better orders are used by traders who want to set up a purchase or sale in advance, so that their brokers can automatically fulfill their order when the price of a security reaches a certain rate without their involvement. At-or-better orders are also used by investors to guarantee that they will not pay more or receive less than for securities than the price they want.
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