Anthropic tightens rules: why Claude now blocks game clones
TL;DR
Anthropic has added a passage to the system prompt of Claude Code and Claude Opus 5.5 that rules out recreating specific existing games, even under a new name. Help with games built from your own designs and assets is still allowed, and Anthropic points to possible intellectual property violations. According to reports on GitHub and Reddit, Claude has since also refused reverse engineering, patching game code and even analysing a Windows crash.
Nauti's Take
The clear rule gives legal certainty to anyone building games from their own designs and assets, and it protects studios from quickly cloned prototypes. The catch is false positives: when reverse engineering, crash analysis or patches to code people own get refused too, the block hits exactly the developers who use Claude most productively.
Anyone running game tooling or security analysis through Claude should log refused prompts and keep a fallback ready for now.
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