When you own an option, you have the right to exercise.
Important: You have the right - not the obligation. As previously
mentioned, you are going to be better served to sell your options when
you no longer want to own them. It is seldom a good idea to exercise.
Nevertheless, you should understand the process.
When an option owner notifies his/her broker to exercise an option,
that person is choosing to do what the contract allows. That means a
call owner elects to buy 100 shares by paying the strike price per
share. The put owners elects to sell 100 shares and collect the strike
price per share.
Once exercised, the option no longer exists.
When you exercise an option, someone is on the other end of the
transaction. It is not the person with whom you made the original
trade. All exchange traded options are fungible, and that means they
are identical. If you buy some IBM Oct 110 calls, they are identical
with every IBM Oct 100 call. Thus, when you exercise these call
options, there is no way to find the person with whom you traded.
It's far more efficient for some options to be chosen at random.
That's the job of he Options Clearing Corporation. When they receive
(from your broker) your notice to exercise one or more options, they
randomly choose a 'clearing member' and assign that exercise notice to
them. That clearing member then randomly assigned the exercise notice
to one of its customers - your broker (for example). That broker
randomly assigns that exercise notice to one of its customers.
The only requirement is that the customer have a short position (i.e.,
he/she previously sold) that option and it has neither expired nor
repurchased.
The person assigned that exercise notice must honor the contract. If
it was the sale of a call option, then stock must be sold at the strike
price.
If it is a put option, stock must be bought at the strike price.
If you are assigned, it is noting to fear. Many beginners get upset,
believe something terrible has happened and move into a state of
panic. It's not a big deal - unless it results in a margin call, and
that is easy to avoid by being prepared..
These transactions take place overnight when the markets are closed.
If assigned an exercise notice, there is nothing for you to do. When
you look at your account the following morning, the transaction will
already have taken place and it is irrevocable.