Anthropic Blocks Game Clones in Claude 5.5

Anthropic just added a rule that stops Claude 5.5 from copying any existing game, even under a new name. The change appears in the latest Opus 5.5 update spotted by X user Chasm and confirmed by Addy Osmani. The new rule, listed under the cryptic label 'tengu heron brook', tells Claude to build original games only. It explicitly bans recreating any specific title, even if the user renames it as original. Anthropic says using Claude to infringe IP violates its usage policy and will keep tweaking the balance. Developers have complained that Opus 5.5 can reverse-engineer code, prompting studios to cancel public demos for fear of AI clones. Steam's Next Fest saw demo submissions double, with AI-generated games making up most of the surge. Valve's Tom Giardino warned the platform won't ban AI tools, preferring to make Steam smarter instead. He urged developers to add unique features and personality so their games stay harder to copy. As Osmani puts it, if Claude blocks your own idea, send it his way for a fix.