Hand signaling (open outcry)

Hand signaling, also known as arb[1] or arbing (short for arbitrage), is a system of hand signals used on financial trading floors to communicate buy and sell information in an open outcry trading environment.

The AMEX is the only US stock market to permit the transmission of buy and sell orders through hand signals as of 2003[update].

[2] Traders usually flash the signals quickly across a room to make a sale or a purchase.

Signals that occur with palms facing out and hands away from the body are an indication the gesturer wishes to sell.

The signals can otherwise be used to indicate months, specific trade option combinations or additional market information.