Even if it's bound to an EA profile/EA downloader profile, if your mate has any problems he can contact EA support and get them to deactivate the serial from your account.
I have personal experience of them doing this when I ended up with two copies of Burnout Paradise. They deactivated one from my account, added it to a different account I asked them to and even generated a new (third) serial to do this.
All in all, if your mate experiences any problems he should be fine if he takes the time to ask EA support for help.