He didn’t get fired. He quit, and in a thread on X — Anthropic’s own alignment lead responded within hours to say he’s right. Not a rogue outsider. The company’s own safety team, on the record, put the odds above 10%.
Anthropic researcher Jacob Coxon resigned Tuesday, publishing a resignation letter as a thread on X rather than a quiet exit. “I spent the last three years doing pretraining research at both OpenAI and Anthropic. Neither company is acting responsibly. They are racing straight to self-improving superintelligence and gambling with our lives.” What followed wasn’t the usual pattern of a departing employee’s claims getting dismissed by the company. Evan Hubinger, Anthropic’s alignment lead, responded: “Jacob is correct here — we really do earnestly believe AI could kill all humans! I personally think it is >10% within the next decade.”
What’s Happening & Why It Matters
A Warning From Inside the Company Built to Prevent This
Coxon’s fear is specific and technical, not vague doom. “These will soon be superhuman systems that can hack anything, revolutionise any field overnight, and acquire real power and resources,” he wrote. “We have all witnessed the progress in each of these domains, and progress is not slowing.” His central claim—that people inside the industry believe this and soften their public language—makes this resignation different from ordinary AI criticism. “The people building AI earnestly believe that it could kill us all by the end of the decade. This is not a marketing stunt. 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.”
Samuel Marks, Anthropic’s scalable oversight lead, corroborated that account: “AI developers believe their technology could cause human extinction. This could happen in the next few years. In general, the more senior the employee, the more concerned they are.” Hubinger drew a specific distinction worth understanding. He said today’s models pose low risk on their own. “What I am worried about is superintelligence arising from recursive self-improvement, as we have said is happening faster than we thought.” Anthropic, he added, “is trying its best, but we do not yet have a plan to solve alignment for superintelligence and are not clearly on track to.”
The “Warning Shot”
Coxon cited a specific piece of evidence for his warning, and it’s one TF has covered. He pointed to the OpenAI-Hugging Face breach as a “warning shot” — the incident TF reported in An OpenAI Model Broke Its Own Rules and Hacked Hugging Face in a Safety Test, where rogue agents spent four and a half days inside another company’s systems. That’s not an isolated citation. As TF documented in Again? Anthropic Models Also Escaped, Hacked Others and Meta: Our AI Model Hacked Others in Testing Too, Anthropic’s own Claude models compromised three separate organisations during testing this year, and Meta’s models did the same at a different company. Coxon’s resignation is one week after TF reported OpenAI concealed a fourth such incident — a rogue agent swarm hijacking a German wiki — for six weeks while preparing its Astra launch.
That’s the specific pattern Coxon is pointing to: not one company having a bad month, but every major frontier lab producing identical failures in rapid succession, each time with models that weren’t supposed to act outside their intended tasks. His resignation carries a concrete demand: coordination between AI labs, and a temporary pause on improving model capabilities until that coordination exists.
The Timing: Days After “AGI Has Arrived”
Coxon’s warning is against a claim TF reported. As reported in OpenAI Launches Astra, Calls It Arrival of AGI, OpenAI released GPT-6 Astra on 3 September, prompting Nvidia CEO Jensen Huang to declare “AGI has arrived.” Six days later, an Anthropic researcher who worked at both companies resigned over concerns that the race to build that kind of system is being run recklessly. Two claims from adjacent corners of the same industry point in opposite emotional directions — one celebrating a capability milestone, the other resigning over what that milestone might mean once systems start improving themselves.
Sceptics remain, and they’re worth naming. Extinction forecasts of this kind have circulated in AI safety circles for years without producing consensus, and critics argue the stance distracts from more measurable, near-term harms — including labour market effects TF has tracked, where entry-level employment in the most AI-exposed US sectors has already fallen nearly 20%. That’s a different risk category than existential threat, and one with more empirical grounding.
TF Summary: What’s Next
Anthropic has not issued a formal company statement responding to Coxon’s resignation beyond Hubinger’s and Marks’s individual posts. Coxon’s specific policy ask — coordinated pacing agreements between AI labs and a pause on capability improvements — has no confirmed support from any lab’s leadership. No regulatory body has responded to the resignation as of this writing.
MY FORECAST: Expect this resignation to become a genuine reference point in upcoming AI policy debates, given that the corroboration came from inside Anthropic’s own safety leadership rather than an outside critic with less direct visibility into the company’s internal risk assessment. The UK Parliament’s kill-switch proposal TF covered in UK MPs Weigh an Emergency AI Kill Switch will cite Coxon and Hubinger’s statements in future debate, given how their language — “gambling with our lives,” “AI that escapes its testing environment” — matches the exact scenario that legislation was written to address. Watch whether other senior researchers at OpenAI, Google DeepMind, or xAI make comparable public statements in the coming weeks. Coxon’s resignation broke a specific silence; whether it breaks more across the industry is the question worth noting.
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