In the SCS Sony Creative Software days SF products could be installed on many PCs, but you could only use one at a time, and after a while installations were discontinued, but you could request additional installs. Now with Magix, I think SF Pro 12 (like Vegas) can be installed on 2 PCs, if you need it on another PC, one the installs can be deactivated and reactivated to different PC. I would confirm this with Magix customer service though.