Some times ago me and a friend of mine bought 2 additional warband copies in addition to our basic ones in a steam sale to try some weird skip the fun builds when skip the fun was allowed only with great limitations on mains.
We used one copy to test some build and leave the other one unused and uninstalled, and once chadz announced that he was not allowing anymore the use of secondary keys we got our shared additional key screwed up(we deleted all the chars on it), unusable and ungiftable to anyone(basically rubbish)and we returned to use our main chars
Now I have the other additional warband copy still to be activated on steam(as I said we bought 2 additional copies, one for me and one for him, but we used to use 1 of them for the few weeks we were allowed to use a secondary key)
Basically since I don't need 2 copies/keys of warband anymore I'm trading it(you could use it as a reserve, gift it to your friend that always wanted to try warband, coerce someone you know to earn strategus gold with it to help your faction/ecc)
I was thinking about either 200k gold or a good steam game to be gifted too
The copy still need to be activated and used on a steam account with the a code that I received on my e-mail when I bought it