Exiting a Stock Option Position

Once you own an option, there are three methods that can be used to make a profit or avoid loss: exercise it, offset it with another option, or let it expire worthless. By exercising an option you have purchased, you are choosing to take delivery of (call) or to sell (put) the underlying asset at the option's strike price. Only option buyers have the choice to exercise an option. Option sellers, on the other hand, may experience having an option assigned to an option holder and subsequently exercised.

Offsetting is a method of reversing the original transaction to exit the trade. If you bought a call, you have to sell the call with the same strike price and expiration. If you sold a call, you have to buy a call with the same strike price and expiration. If you bought a put, you have to sell a put with the same strike price and expiration. If you sold a put you have to buy a put with the same strike price and expiration. If you do not offset your position, then you have not officially exited the trade.

If an option has not been offset or exercised by expiration, the option expires worthless. If you originally sold an option, then you want it to expire worthless because then you get to keep the credit you received from the option premium. Since an option seller wants an option to expire worthless, the passage of time is an option seller's friend and an option buyer's enemy. If you bought an option, the premium is nonrefundable even if you let the option expire worthless. As an option gets closer to expiration, it decreases in value.

It is important to note that most options traded on U.S. exchanges are American style options. In essence, they differ from European options in one main way. American style options can be exercised at any time up until expiration. In contrast, European style options can be exercised only on the day they expire. All the options of one type (put or call) which have the same underlying security are called a class of options. For example, all the calls on IBM constitute an option class. All the options that are in one class and have the same strike price are called an option series. For example, all IBM calls with a strike price of 130 (and various expiration dates) constitute an option series.