Mauricio confirmed it for me, an answer I got from Microsoft NZ was ambigious. Searching google for the answer presents this:

 

 

 

"This is from the MS license agreement agreed to when you installed or activated Windows upgrade--

 

What about upgrading the software? The software covered by this agreement is an upgrade to your existing operating system software, so the upgrade replaces the original software that you are upgrading. You do not retain any rights to the original software after you have upgraded and you may not continue to use it or transfer it in any way. This agreement governs your rights to use the upgrade software and replaces the agreement for the software from which you upgraded. "

 

 

 

There's lots of articles about folks imaging windows 7, upgrading to 10, installing to an SSD then restoring their windows 7 partition so they can retain both OS's. Ah well - at least I know my machine runs Win10 nicely, I'll source a legit license key for win10.

 

 

 

Source here: http://answers.microsoft.com/en-us/windows/forum/windows_10-windows_install/free-upgrade-from-windows-7-to-windows-10-dual/29b232b2-ac67-45d6-be88-ac14b0c7bf8e?auth=1

 

 

 

A