I use Paralells now since version 8 and bought every update. I always used on my two machines, one MacBook pro and one stationary Mac Pro. Since Version 13 I'm prompted to deactivate it one of the machines. Is there really a change in licensing? Do I have to buy two licenses for my two machines now? Cant't believe really, because every major software (Adobe CC, Microsoft Office, all Apple Stuff like Final Cut) allows this.