ms licensing

I have an windows 7 ultimate upgrade disc that I bought at the university while I was studying there. I used it on my computer years ago.

The question: My brother has a new computer for his business that is Windows 8 and he wants windows 7 on it. Could I use my upgrade disc for a second time? Will it pass validation?

EDIT 1. I know technically it is a "student" disc, so it crosses the line there a bit. And honestly, I used it on the first computer as a clean install (simply installed it twice from the $30 upgrade disc and got a brand new version of 7 ultimate).

But I don't want to 7 and not have it pass validation, because then I won't be able to revert back to 8 (especially if I do a clean install).

EDIT 2. It's just always unclear to me. I have a student copy of office pro 2007 and have used it for countless people. They don't seem to care.... or do they...?

Jam it back in, in the dark.