Chapter 02 · Section 2.1
The expiration date
The expiration date is the date on which:
a) the option holder must exercise.
b) the option writer's obligation expires.
c) the option holder's rights expire.
The option holder has the right - and not the obligation - to buy (if a call) or to sell (if a put) the underlying asset at a specified price until the expiration date.
An option contract gives the holder a right and the writer an obligation. When the contract matures, the holder's right and the writer's obligation expire. When the contract matures, the holder's right and the writer's obligation expire.