Anthropic’s Fable 5 Ban Sparks Global Concern: Former US AI Adviser Questions Safety Practices, Europe Revives Sovereign AI Call

Anthropic pulled its Mythos and Fable 5 AI models after the U.S. government ordered it to suspend access to them for foreign nationals.

• Anthropic says the alleged security threat was minor and already exists in public AI models.
• Anthropic and the U.S. government are already fighting in courts after friction over the AI company refusing the blanket use of its technology in warfare.
• Anthropic filed IPO papers confidentially last month.

Anthropic’s decision to withdraw its Mythos and Fable 5 AI models after U.S. authorities raised security concerns has reignited fears over the risks posed by frontier AI systems, raised calls for sovereign AI technology, and thrown the IPO-bound company into crisis mode, according to reports and commentary on X.

Anthropic said on Friday it will "abruptly ​disable" its most advanced AI models for all users after the U.S. government ordered it to suspend access to the models for foreign nationals, citing national security ‌concerns.

The company said the government believes there is a method of bypassing, or "jailbreaking" Fable 5 for potential hacking and has issued an export control directive. In a blog post, Anthropic argued that it has reviewed the vulnerabilities it was presented and “these vulnerabilities all appear relatively simple, and we have found that other publicly-available models are able to discover them as well without requiring a bypass.”

Anthropic said it is complying with the order but “disagree[S] that the finding of a narrow potential jailbreak should be cause for recalling a commercial model deployed to hundreds of millions of people.”

Why Is Anthropic’s New AI In Focus?

Anthropic’s Mythos has been the subject of wide attention recently, especially since the company itself admitted that it is significantly powerful and can cause harm, including cyberattacks, if it gets into the hands of malicious actors. 

Earlier this week, the company rolled out an ‌AI model named ⁠Claude Fable 5, representing a new tier of capability it calls "Mythos-class," to a select group of enterprise customers. The model is accompanied by guardrails barring its use in risky areas such as cybersecurity.

The development complicates an already frail relationship between the company and the U.S. government. The U.S. government in March deemed Anthropic a "supply chain risk" after the company refused to allow the U.S. military to use its ​AI technology for domestic surveillance and fully autonomous weapons systems.

Anthropic is suing the Pentagon following the designation and a U.S. judge has ruled the Pentagon's directive could not be enforced.

On Sunday, the Wall Street Journal reported that Anthropic has dispatched top technical staff to Washington over the weekend in pursuit to discuss the issue with the government, after lengthy calls with officials on Saturday.

The discussions included Commerce Secretary Howard Lutnick and National Cyber Director Sean Cairncross as well as Tom Brown, an Anthropic co-founder who is the company’s chief compute officer, and Sarah Heck, the company’s head of public policy, the Journal reported, citing its sources.

Mythos, Fable Ban Revives Sovereign AI Debate

In a long post on X, President Donald Trump’s former AI and crypto advisor, David Sacks, alleged that Anthropic’s response is bewildering.

“A highly credible trusted partner of both Anthropic and the USG who was testing Fable came forward with a jailbreak of those guardrails. The Admin asked Dario to fix the jailbreak or de-deploy the model. Dario refused,” Sacks wrote.

“It is frankly bewildered that Anthropic hasn’t wanted to comply with safety requests that it previously said were its highest priority,” he said, adding that the government action is unrelated to the ongoing legal case. “The ball is in Anthropic’s court.”

Meanwhile, UK Prime Minister Mark Carney said the U.S. export ban on Anthropic’s models shows the risk of depending on a handful of powerful AI tools, reigniting calls for nations to develop their own frontier AI systems. 

“Nobody’s done anything wrong in this situation, but we will have done something wrong if we just accept this, don’t take the lesson, don’t build out and diversify,” Carney told reporters on Sunday, according to a Bloomberg report.

Similarly, the European Union, which gained access to Mythos earlier in June after weeks of talks, said the latest development further underlined "Europe's need for technological sovereignty." 

Anthropic IPO Could Face Headwinds, Retail Remains Upbeat 

The development may complicate Anthropic’s path to an initial public offering. Anthropic confidentially filed for a U.S. IPO last month, edging ahead of rival OpenAI in the race to reach public markets.

On Stocktwits, the retail sentiment for ANTHZZX was ‘bullish,’ with traders saying that the development in fact shows the technology prowess and importance of Anthropic’s technology.

“Anthropic is so superior to all the rest of the AI’s that the United States can’t afford to have it in foreign hands,” a trader wrote. 

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