A contract giving the holder the right to buy or sell a stated number of shares (normally one hundred) of a particular security at a fixed price within a predetermined period. The Paris market has three main types of option: prime, option and stellage Prime is a call option. If the purchaser decides not to exercise his option (because the price has gone down), he merely has to pay the seller a fee, called a don't, the rate of which is fixed by the Chambre syndicale des agents de change. Option is more similar to the U.S. system and can be a put or call option. The purchaser pays a premium (avec), which is negotiated, whether he exercises the option or not. Stellage is the equivalent of the U.S. straddle.