https://support.gog.com/hc/en-us/articles/360001942753-FAQ-Downloads-and-streaming joseS95: jmaebe:
Not really. It is DRM free. While you play LAN at your house in your computers it is fine.
Technically, it works, yes, since there is indeed not any form of DRM. Still, license-wise, you should buy two copies because a single license is only valid for running a single copy of the game at a time (even if it's all at your own place).
"Can I enjoy my purchases both on my laptop and desktop computer at home?
Yes. We do not limit the number of installations or reinstallations, as long as you install your purchased games on computers in your household. So yeah, if you've got a render-farm in the basement, you might actually break the world record for the number of legal Witcher installations in one household. However, if you think about installing your game on a friend's machine or sharing it with others then please don't do it, okay?The same principle applies to movies - you're free to watch them anywhere you want, with anyone you want, as long as you don't share them with people who haven't purchased them."