AI researcher Jacob Coxon says he quit Anthropic after four months, two months before his equity would have vested; he still has equity in prior employer OpenAI (Madison Mills/Axios)

Anthropic researcher Jacob Coxon resigned from the AI lab two months before his equity would have vested, according to Axios. Coxon told Axios that he no longer has anything to gain by boosting Anthropic's valuation. His post on X, which now has over 115 million views, stated that AI could end humanity by the end of the decade. Other AI researchers from Google have also resigned over safety concerns, but they did so after years of work and after their stock vested.

Coxon, who worked at Anthropic for just four months, had to be there for six months for his stock to vest. He still owns equity in his prior employer, OpenAI. Coxon expressed concern about the pressure to race in AI development and the potential for cutting corners or skipping steps in oversight processes. He also noted that recent cyber incidents across frontier AI labs suggest that the danger is real.