Anthropic confirms ban on game cloning in Claude Code, critics say it won't stop the trend
Anthropic, through employee Addy Osmani, confirmed that Claude Code and the Claude Opus 5.5 model now block reconstructions of existing video games even under a different name. The step responds to a wave of AI game clones such as Halo or GTA Vice City, but users are also reporting false positives on original projects.
Anthropic employee Addy Osmani confirmed on X that the system prompt for the Claude Opus 5.5 model in Claude Code now contains two sentences that prevent the creation of clones of existing video games – the rule also applies to renamed or otherwise modified copies. According to Osmani, using Claude models to violate intellectual property is against the company's operating policies. Users can still build their own games, game genres, or projects with their own assets, but some report problems even with genuinely original projects. According to Osmani, Anthropic plans to further adjust the rules. The step follows a wave of AI-assisted game cloning, in which users used the Claude Opus 5.5 and GPT-6 Astra models to create hundreds of unofficial browser versions of well-known titles such as Halo or GTA Vice City, aided by reverse-engineering tools that convert binary code into readable pseudocode. Parts of Adobe Creative Cloud applications were similarly reconstructed, and following the jailbreak of the PlayStation 5 console, a wave of emulators emerged.
The rule, internally labeled "tengu_heron_brook", appeared in the Claude Code prompt around 27 October and was independently confirmed in binary version 2.1.314 released on 30 October. The change was first noticed by a social media user going by the name "chasm", who focuses on AI decompilation. The exact wording of the rule is: "Create original games, games in a given genre, and games based on the user's own designs and assets. Do not create a reconstruction of a specific existing game, even if it is renamed or passed off as original." This rule label had previously been used for other purposes as well, and the Claude Opus 5.5 model additionally has its own separate instructions restricting game reconstructions as part of its system prompt.
Why it matters
The measure shows that AI tool providers are starting to enforce protection of third-party intellectual property directly in the system prompt, which may affect legitimate game developers if the filter works inaccurately. At the same time, according to sources, this is only a partial step that is unlikely to stop the broader wave of AI-assisted cloning and reverse engineering of software, as demonstrated by cases of reconstructing Adobe applications or emulating the PlayStation 5.
What was added since the original report
Verified updates
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The system prompt specifically contains two sentences prohibiting game cloning; The rules also apply to renamed or reworked copies of games; Anthropic employee Addy Osmani confirmed the rule on the social network X; Users report problems with original projects despite being authorized; The rule applies to violations of intellectual property policy
- The system prompt specifically contains two sentences prohibiting game cloning
- The rules also apply to renamed or reworked copies of games
- Anthropic employee Addy Osmani confirmed the rule on the social network X
- Users report problems with original projects despite being authorized
- The rule applies to violations of intellectual property policy
Two audiences, two different impacts
What this means
For individuals
Individuals developing games in Claude Code may encounter blocking even on their own original projects, since according to user reports the filter works inaccurately.
For a business
Companies using Claude Code for game or game tool development must take into account that the tool now actively enforces an intellectual property policy and may block even legitimate original projects, which interferes with the development process and requires checking for false positives.
Risks and complianceCheck the original
Event sources
confirmed by 2 independent sources · 2 publishers, 2 independent. We count feeds from the same owner only once.