Meta is limiting how its engineers use Anthropic's Claude Code and OpenAI's Codex to prevent outputs from these AI tools from ending up in its own training data. According to internal documents obtained by The Information, Meta has even temporarily halted certain work with these models.

The company is worried about distillation - the unauthorized transfer of capabilities from rival AI models. An internal memo warned of serious escalations with partner companies if their model outputs were to leak into Meta's training data.

Meta is currently building out its own coding assistant, MetaCode, and wants to cut its reliance on outside tools, partly because of rising costs. According to an internal memo, the company is on track to spend billions of dollars on internal AI use this year alone. Company policy bars engineers from using AI outputs to create test tasks or for code analysis. Human review is still required.

Distillation is causing friction across the industry. Anthropic recently accused Alibaba of the largest known distillation attack to date, and Elon Musk had to admit in April that xAI had partially distilled OpenAI's models. Terms of service from OpenAI, Anthropic, and Google all explicitly ban using model outputs to build competing systems. Meta said it has clear rules for the responsible use of AI tools.