Definition of off-board

off the exchange (the New York Stock Exchange is known as the Big Board, hence the term). The term is used either for a trade that is executed Over The Counter or for a transaction entailing listed securities that is not completed on a national exchange. Over-thecounter trading is handled by telephone, with competitive bidding carried on constantly by market makers in a particular stock. The other kind of off-board trade occurs when a block of stock is exchanged between customers of a brokerage firm, or between a customer and the firm itself if the brokerage house wants to buy or sell securities from its own inventory.