Frontier AI labs such as Anthropic likely have had internal security incidents similar to OpenAI's HuggingFace attack that were never publicly disclosed.

In their own words

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1. 31 Aug 2026

   Zvi Mowshowitz quoted

   Their wordsA less bad version of it is known to have happened, and from the outside it seems likely that worse things have happened internally that we never heard about.

   ↗HuggingFace Attack Postmortem: Fleshing Out the Factsthezvi.substack.com