Warner Bros has announced it will be offering full refunds for the Steam release of Batman: Arkham Knight through the rest of the year.
The company will offer refunds on the both the full game and its season pass until the end of 2015.” Here's the full statement, as well as a clarifying customer service note by Valve:
We are very sorry that many our customers continue to be unhappy with the PC version of Batman: Arkham Knight. We worked hard to get the game to live up to the standard you deserve but understand that many of you are still experiencing issues.
Until the end of 2015, we will be offering a full refund on Batman: Arkham Knight PC, regardless of how long you have played the product. You can also return the Season Pass along with the main game (but not separately). For those of you that hold onto the game, we are going to continue to address the issues that we can fix and talk to you about the issues that we cannot fix.
Warner Bros Interactive Entertainment
EDIT BY VALVE: For users still running into playtime based refund rejections, we are looking into what is causing those. Please wait to re-submit your refund until we have this resolved. Thank you.