Anthropic adds Claude Code rule barring recreations of specific existing games

What happened

Anthropic has added a rule to Claude Code barring it from recreating specific existing video games. The rule, spotted in Claude Code on October 27 under the heading "tengu_heron_brook," reads: "Do build original games, games in a genre, and games from the user's own designs and assets. Do not build a recreation of a specific existing game, even if it is renamed or called original." Users cannot disable the rule.

Confirmation

Anthropic member of technical staff Addy Osmani confirmed on October 30 that the company added two sentences to Claude Code's prompt on Opus 5.5 "to steer it away from recreating someone else's specific game because using Claude to infringe IP is against our usage policy." Original games, genre games, and games built from the user's own designs and assets are meant to keep working.

Context

The move follows fear among independent developers that AI tools could produce fast-follow clones of their games, in some cases before the original reaches market; Digital Sun Games cancelled a public playtest of its upcoming game ReVamp over clone fears, and developers have pressed Valve on preventing clones on Steam.

Caveat

The rule is a prompt-level steer, not a technical block: Game Developer notes it may only deter low-effort copycats and that it is unclear how the tool judges whether a user owns a game idea or assets.