Spread trade

In finance, a spread trade (also known as relative value trade) is the simultaneous purchase of one security and sale of a related security, called legs, as a unit. Spread trades are usually executed with options or futures contracts as the legs, but other securities are sometimes used. They are executed to yield an overall net position whose value, called the spread, depends on the difference between the prices of the legs. Common spreads are priced and traded as a unit on futures exchanges rather than as individual legs, thus ensuring simultaneous execution and eliminating the execution risk of one leg executing but the other failing.

Spread trades are executed to attempt to profit from the widening or narrowing of the spread, rather than from movement in the prices of the legs directly. Spreads are either "bought" or "sold" depending on whether the trade will profit from the widening or narrowing of the spread.

The volatility of the spread is typically much lower than the volatility of the individual legs, since a change in the market fundamentals of a commodity will tend to affect both legs similarly. The margin requirement for a futures spread trade is therefore usually less than the sum of the margin requirements for the two individual futures contracts, and sometimes even less than the requirement for one contract.

Calendar spreads are executed with legs differing only in delivery date. They price the market expectation of supply and demand at one point in time relative to another point.

A common use of the calendar spread is to "roll over" an expiring position into the future. When a futures contract expires, its seller is nominally obliged to physically deliver some quantity of the underlying commodity to the purchaser. In practice, this is almost never done; it is far more convenient for both buyers and sellers to settle the trade financially rather than arrange for physical delivery. This is most commonly done by entering into an offsetting position in the market. For example, someone who has sold a futures contract can effectively cancel the position out by purchasing an identical futures contract, and vice versa.

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