How many computers can I install Halo 2V on?

I have a question, How many computers can I install Halo 2 PC onto.
I have a physical copy in disc form, and I was wondering if it was like most Microsoft products and can only be installed on 1 - 3 devices?
It’s really bugging me.

You can install it five times: http://www.bungie.net/Forums/posts.aspx?postID=67126084

Thank you, that really helped.