Each September, a who’s who of executives from across Silicon Valley descends on San Francisco’s Palace Hotel to charm investors at a conference hosted by the investment bank Goldman Sachs.

This past week, between talk of growth and potential returns, tech titans found themselves addressing the abrupt resignation of Anthropic researcher Jacob Coxon.

Coxon, a 27-year-old who worked at OpenAI before joining its chief rival Anthropic, said on Tuesday that people building artificial intelligence (AI) believed the technology could destroy humanity.

They are “gambling with our lives”, he said, “these will soon be superhuman systems that can hack anything”.

Coxon is by no means the first AI insider to publicly sound the alarm. There have been a string of high-profile resignations from both Anthropic and OpenAI in recent years over apparent safety concerns, and some current Anthropic employees even echoed Coxon’s post.

“We really do earnestly believe AI could kill all humans! I personally think it is >10% within the next decade,” a team lead at Anthropic, Evan Hubinger, posted on X.

While Coxon said explicitly in his posts that his warnings were “not marketing”, some executives and investors in Silicon Valley have reacted with scepticism to a recent flurry of insiders sounding the alarm.

Anthropic and OpenAI are reportedly preparing for potentially record-setting initial public offerings, and some in the tech sector have suggested the latest stark comments about the dangers of AI may be designed to generate hype by signalling the power of these products.

Anthropic’s boss, Dario Amodei, has come under fire for saying AI technology could wipe out half of entry-level white-collar jobs and will “test who we are as a species”.

One conference speaker, Grindr CEO George Arison, told the BBC he believed this week’s comments from Coxon and others were indicative of an “anti-civilisational worldview at Anthropic”.

He called them “dangerous” and said they had prompted him to instruct some engineers at the LGBTQ+ dating app to stop using Anthropic’s technology.

“It is irresponsible for us as stewards of our shareholders’ money to be relying on a business that does what this company does, in terms of its public statements,” he said.

“Maybe they actually believe it,” Arison said. “Or you could argue they’re saying it because it’s a great way to gin up more investor support, because the only way to justify these valuations is to actually claim: ‘I’m going to take over every industry and I’m going to take over every job, and my AI is going to be doing all that work.'”

Anthropic was valued at $965bn (£713bn) in its most recent fundraising round earlier this year.

The BBC has asked Anthropic for a response to the statements.

In an essay posted early on Saturday, Amodei called for a slowing of AI model development and global regulation – and said the risks associated with AI were “serious”.

Nvidia boss Jensen Huang also discussed Coxon’s comments before a crowd at the conference, multiple people in the group told the BBC. They said he dismissed them as untrue.

Huang has previously said the notion that AI “is going to be the end of humanity” is “complete nonsense”.

And while he may have a business interest in an AI boom – Nvidia builds chips that power AI systems – his comments reflect a growing backlash in Silicon Valley to the existential warnings from current and former staffers.

Some critics have even accused Anthropic of fearmongering in hopes that it will trigger a regulatory push that could shut out competition and leave it and OpenAI with a monopoly in the sector.

Brad Gerstner, who is the head of the investment firm Altimeter Capital, posted pictures of Huang from the conference and accused Coxon of “ridiculous hyperbole”.

On Friday, the CEO of the AI platform Hugging Face, Clement Delangue, weighed in. Hugging Face, which Nvidia announced it would acquire last week, was hacked by OpenAI agents earlier this year prompting an outcry over AI safety.

“Sorry, but asking Jacob about AI extinction risk is like asking your AC guy about climate change,” he wrote on X. “Not saying it’s necessarily uninteresting or wrong per se but let’s keep things in perspective.”

Both Gerstner and Delangue were more circumspect on Saturday after Amodei’s proposal was posted, with Gerstner calling the idea “an important step forward” in balancing competing considerations like speed and safety.

Delangue offered to help be a part of the potential solutions proposed by Amodei.

In April, Anthropic roiled the AI world when it said it found that its Mythos tool could outperform humans at some hacking and cybersecurity tasks.

Mythos also showed the ability to independently escape what is known as the sandbox environment, setting off a debate among regulators, legislators and businesses about AI’s potential dangers.

In a new development on Thursday, Anthropic said it had found and stopped threat actors who were trying to use its AI technology for activity including the development of bioweapons and cyber-espionage.

Beneath the sparkling chandeliers hanging in the stained-glass dome atrium of The Palace Hotel, some investors told the BBC that the comments from Coxon and others could accelerate a government crackdown.

Federal legislation co-sponsored this month by left-wing Senator Bernie Sanders of Vermont, known as the Ban Artificial Superintelligence Act, would impose a temporary pause in advanced AI development.

“There is a good chance that human beings will lose control over AI,” Sanders told the BBC’s Newsnight programme on Thursday. “And what happens then, nobody knows. But could it be catastrophic? Yes, it could.”

“When scientists tell you there is a chance that it could have a cataclysmic impact on humanity, you’ve got be a moron not to say, slow it down,” he added.

If an industry-wide government crackdown comes, however, it is likely to be led by legislators and not the Trump administration which largely supports a policy of unfettered AI development. It has framed this as necessary to ensure the US does not cede dominance to China.

Speaking to reporters this week, President Donald Trump was asked if he had any concerns about AI leading to human extinction. “No, I don’t have any,” he said. “I have concerns that if we don’t win AI, we’re going to be put in a very bad position. We are leading China right now.”

But the president’s relationship with Anthropic has been turbulent. After the company refused to allow the US military to use its AI models, the White House described it as “a radical left, woke company” and designated it a supply chain risk, a move that a federal judge has ruled was illegal.

David Sacks, Trump’s AI czar in the early days of his administration, has also levelled repeated attacks at Anthropic.

OpenAI has not endured the same level of scrutiny from the White House. When releasing a new model called Astra last week, OpenAI President Greg Brockman described his firm’s relationship with the Trump administration as “a very good partnership”.

OpenAI, which announced in June that it would go public on the stock market, was most recently valued at $852bn.

The company did not respond to a BBC inquiry seeking comment.

At the conference in San Francisco this week, the pursuit of fortunes seemed to mostly trump any mounting existential concerns or fears over potential government restrictions on AI.

One investor said he was looking forward to Anthropic’s forthcoming S-1, a document a company must file with securities regulators in order to sell shares.

His main question about the company was simple: is the firm profitable?

When asked on Thursday if he fears the world may be coming to an end, Sid Sheth – CEO of the chip company d-Matrix which inked a deal with Nvidia at the conference that day – did not mince his words.

“No,” he said.

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