Option (finance)

Option (finance)

In finance, an option is a contract which gives the owner the right, but not the obligation, to buy or sell an underlying asset or instrument at a specified strike price on or before a specified date. The seller incurs a corresponding obligation to fulfill the transaction, that is to sell or buy, if the long holder elects to "exercise" the option prior to expiration. The buyer pays a premium to the seller for this right. An option which conveys the right to buy something at a specific price is called a call; an option which conveys the right to sell something at a specific price is called a put. Both are commonly traded, though in basic finance for clarity the call option is more frequently discussed, as it moves in the same direction as the underlying asset, rather than opposite, as does the put.

Options valuation is a topic of ongoing research in academic and practical finance. For simplicity of discussion, the value of an option is commonly decomposed into two parts: The first of these is the "intrinsic value," which is defined as the difference between the market value of the underlying and the strike price of the given option. The second part depends on a set of other factors which, through a multi-variable, non-linear interrelationship, reflect the discounted expected value of that difference at expiration. Although options valuation has been studied at least since the nineteenth century, the contemporary approach is based on the Black–Scholes model which was first published in 1973.

Options contracts have been known for many centuries, however both trading activity and academic interest increased when, starting in 1973, options were issued with standardized terms and traded through a guaranteed clearinghouse at the Chicago Board Options Exchange. Today many options are created in a standardized form and traded through clearinghouses on regulated options exchanges, while other over-the-counter options are written as bilateral, customized contracts between a single buyer and seller, one or both of which may be a dealer or market-maker. Options are part of a larger class of financial instruments known as derivative products, or simply, derivatives.