I traded a Dota 2 item for Witcher 2 key through steam (that is, I traded my item through steam, then he just gave me the key and the link to redeem it here at gog) with a guy with a lot of good rep, but I just wanted to make sure trading GOG keys is "allowed". He said it was unused, so I dunno if he got it as a gift or w/e, but if it was already used it wouldn't work right?

I mean like, if he bought it retail, and has it installed, it wouldn't let me use the key as well right?

Just wanted to make sure.

thanks guys.

Does sound a little fishy, but can you see the Witcher 2 in your Account here? Or, can you redeem your key successfully here? - http://www.gog.com/en/witcher2/backup/

Ya I redeemed it successfully, I just wanted to make sure though that I'm not playing off his key... i.e. is it possible both he and I have it both installed with that key simultaneously?

After re-reading your original explanation, this doesn't sound right. What is to stop anyone from re-selling / trading their game a hundred times?

Just your own personal ethics, I guess.

That's why I'm asking, I'm worried that he might have just given me the CD key he used to install the game with.

If he has it installed on his computer (presumably retail), would it still have allowed me to redeem the key here at GOG and install it on mine?

Anyways, I wrote GOG, hopefully they can give me an answer since they're CDProjekt's sister company or so I've heard.

If you have a retail copy, yes - you can redeem your key for a GOG version of the game. I guess if you were to sell the game (your key) - the expectation is that you would delete the game from your hard drive and not use it anymore.

At any rate - enjoy the game. Lots of replayability.