AI

Meta restricts Claude Code and Codex due to distillation fears

3 min read
Photorealistic depiction: in a Meta office, a manager pushes a barrier with a "Restricted" sign in front of workstations whose monitors show the Claude and OpenAI Codex logos. Image generated with GPT Image 2
Photorealistic depiction: in a Meta office, a manager pushes a barrier with a "Restricted" sign in front of workstations whose monitors show the Claude and OpenAI Codex logos.

TL;DR Too Long; Didn’t read

Meta is reportedly limiting the use of Anthropic's Claude Code and OpenAI's Codex by its own engineers, according to internal documents reviewed by The Information, to prevent outputs from these tools from unintentionally flowing into its own training data (distillation). An internal memo instructed teams to suspend certain tasks with the tools, out of concern for escalations with partner companies. Meta is simultaneously expanding its own assistant MetaCode and aims to cut costs. The issue of distillation is causing tensions industry-wide: Anthropic accuses Alibaba of the largest known distillation attack to date (28.8 million interactions via 25,000 fake accounts), and Elon Musk admitted under oath in April 2026 that xAI had partially distilled OpenAI's models.

Key takeaways

  • Meta is reportedly limiting the use of Claude Code and Codex by its own engineers according to internal documents reviewed by The Information.
  • The reason is concern about unintended distillation: outputs from competing models could flow into Meta's training data and trigger escalations with partner companies.
  • An internal memo instructed teams to temporarily suspend certain tasks with the external tools; AI outputs may not be used for testing tasks or code analysis.
  • Meta is simultaneously expanding its own coding assistant MetaCode and aims to cut costs, which according to an internal memo are expected to reach billions of US dollars this year.
  • Anthropic accuses Alibaba of the largest known distillation attack to date: around 28.8 million interactions with Claude via 25,000 fake accounts.
  • Elon Musk admitted under oath in April 2026 that xAI had partially distilled OpenAI's models – evidence of how widespread the practice is in the industry.

Meta restricts the use of Anthropic’s Claude Code and OpenAI’s Codex by its own engineers, according to internal documents. The reason is the concern that outputs from these external AI tools could unintentionally flow into Meta’s own training data – a process known in the industry as distillation.

What Meta restricts according to the documents

According to The Information, which was able to view internal guidelines, the restrictions mainly affect engineers in Meta’s “Applied AI” department, which is responsible for building Meta’s own coding assistant, MetaCode. An internal memo reportedly instructed individual teams to temporarily suspend certain tasks using Claude Code and Codex. As reported by TheNextWeb, the memo warned that outputs from competing models could “leak” into Meta’s training data, potentially triggering “serious escalations with partner companies.” Specifically, AI outputs are not allowed to be used for creating test tasks or for code analysis; human review remains mandatory in any case.

Why distillation becomes a problem for Meta

Distillation refers to a training method where a smaller or cheaper model learns from the outputs of a stronger, usually external model – without directly copying the source code, weights, or training data of the original model. For a company that is simultaneously developing its own models and using competitors’ tools in everyday work, a structural risk arises: If code suggestions, architectural decisions, or debugging logic from Claude Code or Codex inadvertently flow into internal training pipelines, documentation, or synthetic training data, the capabilities of competing models could indirectly transfer into Meta’s own Llama model family. The terms of use of OpenAI, Anthropic, and Google explicitly prohibit using model outputs to train competing systems.

Cost pressure as a second driver

In addition to the distillation concern, the reports also highlight the cost factor: Meta wants to reduce its dependence on the relatively expensive external tools and is reportedly on track to spend billions of US dollars on internal AI usage alone this year. Meta is not alone in this – other large tech companies are also exploring cheaper alternatives in light of rising prices for AI coding tools. Meta stated to The Information that it has established clear rules for the responsible use of AI tools.

Distillation as an industry-wide contentious issue

The topic of distillation is currently causing significant tensions in the industry beyond Meta’s individual case. According to a letter viewed by CNBC to the US Senate, Anthropic accused the Chinese technology company Alibaba of conducting over 28.8 million interactions with Claude through around 25,000 fraudulently created accounts between April 22 and June 5, 2026, to specifically extract its advanced capabilities in software development and agentic reasoning. Anthropic described this as the largest known distillation attack on its company to date. Alibaba did not comment in detail on the allegations, according to CNBC.

The issue also recently attracted attention at a US competitor: In the legal dispute between Elon Musk and OpenAI, Musk reportedly admitted under oath during his testimony in April 2026, according to Forbes, that his company xAI had “partially” distilled OpenAI’s models to train its own systems. When directly asked by an OpenAI lawyer, Musk initially gave a vague answer, stating that AI companies generally distill each other’s models, before specifically confirming the practice for xAI.

Assessment

The Meta case illustrates a dilemma that an increasing number of AI companies must face: In order to develop competitive tools in-house, engineers often rely on the already mature products of competitors – thereby creating the very dependency that is supposed to be reduced. At the same time, the series of allegations surrounding Alibaba and xAI makes clear that distillation is no longer just a theoretical risk, but leads to tangible diplomatic, legal, and political disputes between the major AI providers.

Frequently asked questions

What does distillation mean in the AI context?

Distillation refers to a training method where a smaller model learns from the outputs of a larger, usually foreign model, without directly copying its source code or training data. The terms of use of major AI providers explicitly prohibit using model outputs to train competing systems.

What specific restrictions apply at Meta?

According to internal documents that The Information was able to review, engineers in Meta's Applied-AI department are not allowed to use AI outputs from Claude Code and Codex to create testing tasks or for code analysis; individual teams have also been instructed to temporarily suspend certain tasks with these tools.

Why does Meta want to become more independent from Claude Code and Codex?

Meta is building its own coding assistant with MetaCode and aims to reduce dependence on the more expensive external tools. According to an internal memo, the company is on track to spend billions of US dollars on internal AI use this year alone.

What exactly does Anthropic accuse Alibaba of?

Anthropic accuses Alibaba of conducting more than 28.8 million interactions with Claude through around 25,000 fake accounts between April and June 2026, to extract its capabilities in software development and agentic reasoning – according to Anthropic, the largest known distillation attack on the company to date.

What did Elon Musk say about xAI and OpenAI models?

In the legal dispute between Elon Musk and OpenAI, Musk admitted under oath in April 2026 that xAI had 'partially' distilled OpenAI's models to train its own systems, after an OpenAI lawyer had directly asked him about it.

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