could i use a usb to install windows to more than one pc?

[DarqFX]

So the situation is this: I have windows 10 installed on my pc, my friend just recently got a pc but he forgot to buy a windows copy, could i use mediacreationtool and install windows to his pc? i heard that its technically not legal, but if i wanted to, could i?

 

[scout_03]

have him get a legit key no further help on this forum rules.

 

[Dark Lord of Tech]

They can install Windows 10 and use it until they can purchase their key. There are very minimal restrictions , mostly cosmetic adjustments. There will be a watermark in the bottom corner till they purchase and activate the key.