Claude Code now declines to build a copy of a specific existing video game, even when the user changes its name or adjusts the mechanics. There was no announcement; users found the rule by running into it, and an X user was the first to spot the new instruction text. The tool still helps with original games, games within a genre, and games made from a person's own designs and assets.
“Do not build a recreation of a specific existing game, even if it is renamed or called original.”
new instruction text added to Claude, as found by an X user, reported by Engadget · engadget.com ↗
The change was first noticed around 27 October. It is applied on Anthropic's servers rather than in the installed tool, so users cannot switch it off, and Crypto Briefing reports that it sits behind an internal flag named tengu_heron_brook. A post about it on 30 October drew hundreds of thousands of views. Anthropic has issued no official statement, and a wider usage policy update due on 12 November 2026 does not mention it.
Addy Osmani of Anthropic confirmed the change on X. He said the aim is to steer the tool away from copying someone else's specific game, since using it to infringe IP breaks the usage policy, and that original and genre games should be unaffected while the company keeps adjusting the balance.
About Claude Code
Anthropic released Claude Code, an agentic terminal tool for handing coding tasks over by prompt, in February 2025, and made it generally available in May 2025 alongside Claude 4. On 20 October 2025 it launched a web version with a sandboxing feature.
The tool went viral over the 2025 to 2026 winter holidays, after Claude Opus 4.5 improved it and many non-programmers tried it for vibe coding. By 12 February 2026 its run-rate revenue was above $2.5 billion, more than double its level at the start of the year, according to Anthropic's funding announcement.
May 2025
Released
Clone worries have been growing. AI-decompiled or vibe-coded browser versions of Halo: Combat Evolved, Call of Duty: Modern Warfare 2 and Grand Theft Auto V have appeared recently, and Digital Sun, maker of Moonlighter, has cut back public playtests of its upcoming ReVamp over fears of copies. Some developers welcome a curb on low-effort clones; others are annoyed and weigh other AI models.
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