Anthropic Researcher Coxon Resigns, Warns of AI 'Endgame'

A 27-year-old Anthropic pretraining researcher told the Wall Street Journal he is leaving the AI industry because he no longer believes any single lab can safely build the systems his employer is racing to build.

Jacob Coxon spent three years on pretraining research, first at OpenAI and then at Anthropic. Announcing his resignation on X, he wrote: 'Neither company is acting responsibly. They are racing straight to self-improving superintelligence and gambling with our lives.'

His timeline is short. 'We're on track for a lot of the most aggressive of these scenarios where by the end of next year things could be out of control already,' Coxon told the WSJ. He said researchers inside frontier labs increasingly use the words 'crunchtime' and 'endgame' to describe where capability progress is headed.

Coxon's argument is not that Anthropic's safety work is fake, but that the competitive race makes it insufficient. He compared today's setup to an older one: 'It's kind of insane that it has to happen on the MacBooks of some engineers living in San Francisco instead of a bunker in the desert like where they were doing the Manhattan Project.' Entering the 'endgame' from inside a private company, he wrote, is 'a hubristic gamble that should not be launched from a private company's Slack.'

The resignation lands days after OpenAI's Pachocki conceded that no lab has solved alignment at the scale it is chasing, and in the same week a proposed class action against Anthropic over its Claude Max usage claims was filed.