Deep Silver is warning players of unauthorized 3rd parties selling Steam keys for Metro Exodus after some were obtained illegally from the factory where physical key printing had taken place.
This is pretty interesting, since illegal key selling is usually associated with transactions carried out online.
It could also be in response to Deep Silver's deal with Epic to exclusively launch the PC version of Metro Exodus on the Epic Games Store, as the developer said the keys were obtained prior to the deal.
As explained on the Metro Exodus discussion board on Steam, the only supported key sellers for the game are Humble Bundle and the Razer store.
"Due to the criminal nature of these keys, all unlicensed keys have been deactivated and activation/download of Metro Exodus without the executable file is no longer possible," the post continues.
"In addition, the software will be removed from the Steam library of any players using an unauthorized code. The keys being sold on this platform are stolen goods, and are therefore illegal."
The developers are encouraging players who have been affected to contact the seller who sold them the unlicensed key and demand a refund.