Anthropic launched Fable 5, its most powerful model yet, on June 9.

Three days later it was gone, and the tip that killed it reportedly came from its largest backer, Amazon.com Inc. (NASDAQ:AMZN).

In evidence of how powerful the new model is, launch partner Stripe reported that Fable 5 ran a codebase-wide migration across a 50-million-line Ruby codebase in a single day, work it estimated would have taken an engineering team over two months. That is the enterprise firepower now sitting dark.

Why Washington Pulled The Plug

Amazon’s researchers cracked Fable 5, reportedly using a “fix this code” prompt to make it surface information useful for cyberattacks.

Its CEO, Andy Jassy, took the findings to Treasury Secretary Scott Bessent and other officials, and on June 12 Commerce Secretary Howard Lutnick ordered Anthropic to pull the model.

Amazon has poured roughly $13 billion into Anthropic and holds a $100 billion cloud commitment from it, yet its own team triggered the crackdown. Amazon said governments routinely seek its security counsel and that AWS was hit, too.

The Department of War had already blacklisted Anthropic as a supply chain risk in February, after the company refused to let the military use Claude for autonomous weapons or mass domestic surveillance.

Officials reportedly threatened controls weeks earlier after the restricted Mythos model reached a foreign entity tied to the Chinese Communist Party. Former AI czar David Sacks said Amodei refused a request to patch or pull Fable, an account the company disputes.

The government order barred every non-U.S. citizen from using Fable, anywhere in the world. Anthropic had no way to check who was American, so it just switched both models off for everyone. Even its own foreign-born engineers got locked out, unable to work on a fix.

What Polymarket Is Pricing

Polymarket gives Fable 5 a 30% chance of returning to U.S. customers by June 19, and a 59% chance by June 26.

The chance of Anthropic beating OpenAI to IPO has fallen from 83% to 62% since the incident.

Anthropic argues the same flaws are reachable on rivals like OpenAI‘s GPT-5.5, which runs unrestricted while Fable sits benched.

Anthropic is private, so the public way to play it is through its two big backers, Amazon and Alphabet Inc. (NASDAQ:GOOGL). Both invested billions and both resell Claude through their clouds, AWS and Google Cloud, so a long Fable outage stings each.

“Big Short” investor Steve Eisman has turned cautious on hyperscalers like Alphabet, wary that their swelling AI spend now leans on shareholders to fund it.

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