Natural Selection 2 developer Unknown Worlds has deactivated 1,341 Steam keys for the game, after a charge-back to their store resulted in a $30,000 fee for the small studio. In a post explaining the situation, they say the keys were bought to be resold through third party sites, likely using stolen credit card information.
"Keys were then sold through a handful of questionable sites to people using legitimate credit cards. The owner of the stolen credit card ultimately disputed the charge and we lost the sale. In total, we lose ~$45 per transaction of this kind, due to the charge-back fee (~$22 fee + $25 game price)."
It's a story with no happy end. Unknown Worlds are now faced with a hefty bill, the ultimate purchasers of the keys are left without access to the game, and the scammers get to keep the money from their various sales. "If your key was deactivated, we recommend you contact the site you purchased it from for a full refund. It's unfortunate that players who believed they were buying legitimate games were hurt by these unscrupulous resellers."
Unknown Worlds stress that there are only two official outlets for copies of Natural Selection 2, Steam and the developer's Humble Store page (which is currently unavailable due to this issue). "If you see Natural Selection 2 available anywhere else — like the many sites out there that sell Steam keys at a discount — then you are not buying it from us and there is no way to know if that key is legitimate. As a result, we strongly discourage purchasing from these sites."
It's a lesson that should probably extend to all digital purchases. A number of sites now offer Steam keys, and often at a cheaper price than either from the developers or the Steam storefront. The trick is distinguishing between perfectly legitimate sites offering good value for money, and dubious resellers with keys from who knows where. It would be good to see more developers taking the time to clarify which digital retailers are authorised to sell their games.