Open outcry

Open outcry is the name of a method of communication between professionals on a stock exchange or futures exchange which involves shouting and the use of hand signals to transfer information primarily about buy and sell orders.An example of a market which uses this system is the New York Mercantile Exchange, which is primarily a futures exchange market (another would be the Chicago Board of Trade). The open outcry system is being replaced by electronic exchanges (e.g. CATS), the supporters of which claim that they are faster, cheaper and more efficient for users, and less prone to manipulation by stock specialists and broker/dealers.
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The method of trading used at futures exchanges, typically involving calling out the specific details of a buy or sell order, so that the information is available to all traders.

Oral bids and offers made in the trading rings, or pits. "Open outcry" is required for trading futures and futures options contracts to assure arms-length transactions. This method also assures the buyer and seller that the best available price is obtained.