modo allows installion on multiple machines,  though only one instance can be opened at any given time.  This is great for folks like me who have accumulated several computers.  The only complaint I have is [begin rant] their insistence on installing Apple's Bon Jour, when in fact it is only needed if you want to render in network.  Apple rigged Bon Jour with locked permissions and hidden files, making it difficult for the average user to uninstall, if you happen to dislike Bon Jour's insistence on running at startup and sucking up CPU cycles and LAN bandwidth unnecessarilly .  I consider it "stalkerware", and it would be wonderful if Luxology gave the modo user the option of whether they want to install it. [/ rant]

Vue will allow installation on one desktop and one laptop, with only one instance running at any time.

Silo allows for installation on any three machines.

LightWave allows installation on multiple machines, with only one instance running at any time.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5