An artificial intelligence researcher has quit Anthropic, accusing both his former employers — OpenAI and Anthropic — of acting irresponsibly in the race to develop advanced AI systems that he says could endanger humanity.
Jacob Coxon announced his resignation on Tuesday after three years of pre-training research at the two leading AI companies. He previously worked at OpenAI from 2023 until July 2026, contributing to models including GPT-4o, before joining Anthropic.
“Neither company is acting responsibly,” Coxon wrote on X. “They are racing straight to self-improving superintelligence and gambling with our lives.”
He claimed that people building AI systems privately believe the technology could cause catastrophic outcomes by the end of the decade.
“The people building AI earnestly believe that it could kill us all by the end of the decade. This is not a marketing stunt,” he said. “If anything, many executives and senior researchers will couch their phrasing in the press to sound sensible — but I hear the same people express fear privately.”
Coxon described a key difference between the two labs: “At OpenAI, many have not deeply internalized the civilizational stakes. At Anthropic, the stakes are well-understood, but they are locked in a race to get there first — they believe no one else will act responsibly, so they must do it themselves, despite the risk.”
Neither OpenAI nor Anthropic responded to requests for comment.
Some current and former colleagues echoed his concerns. Evan Hubinger, who leads Anthropic’s alignment stress testing team, replied: “Jacob is correct here—we really do earnestly believe AI could kill all humans! I personally think it is >10% within the next decade.”
Hubinger added that while Anthropic is “trying its best,” the company does not yet have a plan to solve alignment for superintelligence.
Samuel Marks, an Anthropic safety researcher speaking personally, said some developers believe their technology could cause human extinction “in the next few years,” with more senior staff often more concerned.
The departure follows a series of resignations at frontier AI labs over safety issues, including previous exits from both OpenAI and Anthropic.
