Rockstar Games recently added new anti-cheating measures to Grand Theft Auto 5 in order to address long-standing issues with cheaters in the game. But that move has apparently had some unexpected consequences for gamers who play the title on Steam Deck. GTA 5 is now listed as “unsupported” by Steam Deck, and it may be down to a dispute between Rockstar and Valve.

As reported by The Verge, the Steam Deck compatibility message that comes up with Grand Theft Auto 5 states that “this game’s anti-cheat is not configured to support Steam Deck.” It also warns that “some or all of the game” doesn’t function. What it doesn’t say is that the part that doesn’t work is Grand Theft Auto Online.

In a blog post, Rockstar writes that Steam Deck doesn’t support its anti-cheating BattlEye software for GTA Online. But as noted by The Verge, other titles on Steam Deck have successfully utilized BattleEye. Rockstar has seemingly decided not to work with Valve on the issue despite telling affected gamers that “all technical support questions should be directed to Valve’s Steam Deck support content and community.”

For now, Grand Theft Auto Online functionality has been removed from Steam Deck by Rockstar. The rest of GTA 5’s story mode is still playable despite the “unsupported” tag from Valve. It’s possible that a solution between the two sides can be worked out in the future. But for the moment, this is where things stand. In the meantime, gamers are already looking ahead to the long-awaited sequel, Grand Theft Auto 6, which is scheduled to arrive in Fall 2025.