A version of an artificial intelligence (AI) tool which the company said was too powerful to be released to the public has just been released to the public.
Claude Fable 5 is a version of Anthropic's Claude Mythos, an AI program which caused serious concerns among technology, finance, and government leaders when it was released privately in April for previewing and testing.
Some worry the tool is so powerful it could pose financial security risks, though others have questioned how much of the hype is marketing spin.
Anthropic said on Tuesday Fable will be released with safeguards and user limitations in place, though it said "releasing a model this capable comes with risks".
"Fable's capabilities exceed those of any model we've ever made generally available", it added.
When Mythos was first released to a small group of organisations to preview the tool, Anthropic said it was doing so because the tool was so intelligent that it could be dangerous because of its ability to exploit or hack computer systems.
Canadian Finance Minister François-Philippe Champagne told the BBC in April that the attention on Mythos was warranted, in part, because "it's the unknown, unknown".
Meanwhile, despite Anthropic's ongoing lawsuit against the US Department of Defense over its refusal to accept government use of its AI tools, US government agencies have been testing Mythos too.
Anthropic is expected to become a public company soon, as its private valuation has neared $1tn (£747bn). Consistently showing better and broader AI capabilities underlines its value to investors.
The company also said on Tuesday said that the roughly 150 groups that had been given access to preview Mythos will now have access to Claude Mythos 5, which does not have limitations on cybersecurity or biology, depending on an organization's specific uses.
To-date, groups and companies using Mythos have reported to Anthropic finding more than 10,000 critical security flaws in their systems.
Anthropic said the updated access was limited to a "small group of cyberdefenders and infrastructure providers" but is expected to go beyond that soon.
"We intend to expand access to Mythos 5 through a broader trusted access program", the company said.
Both Fable and Mythos, which are essentially the same model but with different safeguards and levels of access in place, can work "unattended" on human commands that the tools are given for longer periods of time "than any previous Claude models." Anthropic added.
Anthropic co-founder Jack Clark last week told BBC Newsnight that the ability of AI tools was expanding so rapidly that the company thought there should be a way for the public to slow the technology's advancement.
"You want the option to be able to take your foot off the gas and put your foot on the brake", Clark said. "Right now, it's like the AI industry has a gas pedal, but it doesn't have a brake pedal."
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