The license agreement allows you to install your Rhino on all of the computers you directly control, provided you can show your Rhino will only be running on one computer at a time. Rhino is licensed on a “simultaneous use” basis and not on a “per installation” basis.
Here is the detail from the EULA:
“Robert McNeel & Associates grants you the non-exclusive license to use the Software on any computers owned by you so long as the number of simultaneous users does not exceed the number of licenses you own. If you run the Software on a server, the number of simultaneous users must not exceed the number of licenses you own.”