Does my license goes any OS I use?

I would like to know if I purchese a Ruby Mine license, It will can be used on whichever OS I use.

In my case, I use Linux and I'm testing Windows 7 at home and Windows XP at work.

Can I install Ruby Mine in all those  using the same license?

Yes, you can install and use RM on several OS but you cannot simultaneously launch and work with several RubyMine copies with the same license on several OS.