After the rather bad response of the PC-community because of major perfomance problems that even made the game not playable, Warner Brothers and Rocksteady took the game from the market and will start selling it, when the game is completely without those bugs. Gary Lake-Schaal from WB wrote a statement on Steam, apologizing to the fans on PC:
“We want to apologize to those of you who are experiencing performance issues with Batman: Arkham Knight on PC. We take these issues very seriously and have therefore decided to suspend future game sales of the PC version while we work to address these issues to satisfy our quality standards. We greatly value our customers and know that while there are a significant amount of players who are enjoying the game on PC, we want to do whatever we can to make the experience better for PC players overall.”
It is not sure, when the game is available again. Until then, refunds are possible for every player on Steam and probably on most of the retail seller’s websites.