Ok so I’ve been trying to self educate myself on options trading in my free time, and there is something I can’t seem to understand. It seems like a simple way to get risk free instant money, so I KNOW there’s gotta be something I’m missing here.

I’ll use AAPL as an example. right now trading at $99.
If I buy 1 put contract at strike price $120 for $21.40 per share, since this put is already in the money, couldn’t I exercise it immediately? selling 100 shares for $120, minus the $2140 I paid for the option would give me an instant credit of $9905.
This all seems way to simple, so what am I not getting here?

Thanks for the help,
Semper Fidelis

here is a link to AAPL options chart:

http://finance.yahoo.com/q/op?s=AAPL&m=2009-03