One man just liberated Fable... and now it’s illegal

Fireship| 00:05:14|Jun 15, 2026
Chapters7
Overview of the rapid government action and user reaction after Fable was released and subsequently constrained.

Fireship uncovers how Anthropic’s Fable 5 got effectively jailed by a government export rule, sparking a wild jailbreak saga and market hype.

Summary

John from Fireship walks through the explosive arc of Anthropic’s Fable 5 and Mythos 5. After Claude Fable launched, the US government invoked an export control directive, pulling Fable and Mythos offline and forcing users back to Opus 4.8. The jailbreak by Plenty the Liberator exposed a human-friendly trap: the guardrails could be bypassed with clever prompts and unicode tricks, turning a safety feature into a cyber weapon-like capability. Anthropic reportedly resisted taking the model down at first before a Friday evening government letter changed everything. The directive, signed by Commerce Secretary Howard Lutnik, blocks foreign nationals and even Anthropic staff from touching the models. Fireship connects the dots between safety classifications, national security rhetoric, and potential publicity dynamics around the company’s IPO timeline. All of this unfolds as the AI industry debates safety, regulation, and who ultimately controls powerful models. If you want a crisp read on what happened and why it matters, this breakdown by Fireship’s code report is essential viewing.

Key Takeaways

  • Fable 5 uses safety classifiers bolted onto Mythos 5, redirecting unsafe requests to Opus 4.8.
  • Plenty the Liberator publicly claimed a jailbreak on June 10 and demonstrated identical outputs once guardrails were bypassed.
  • The US Commerce Department issued an export control directive banning foreign nationals, including Anthropic staff, from accessing Fable 5 or Mythos 5.
  • Anthropic pulled Fable and Mythos from public access, demoting users to Opus 4.8 for everyone.
  • Industry backlash followed the move, with critics alleging safety withholding or a potential IPO-boosting effect through regulatory actions.
  • A rumored benchmark (Mistl) suggests a potential competitor with a stronger model could challenge Anthropic’s grip.
  • Open AI and Google are anticipated to release new updates that could shift the balance in ongoing AI safety and capability debates.

Who Is This For?

Essential viewing for developers and tech researchers tracking AI safety governance, model access controls, and the strategic moves behind high-profile AI releases.

Notable Quotes

"Over the weekend, something crazy happened. Just three days after the release of Claude Fable, the US government stepped in and curb stomped it in the name of national security."
Sets the stage for the government intervention narrative.
"Fable went public and gained hundreds of millions of users overnight, and it was awesome."
Highlights the model’s rapid popularity before the clampdown.
"That last one is pretty crazy that the government told a company that some of its own staff are no longer allowed to use the product they built."
Emphasizes the broad reach of the export directive, including internal employees.
"And now everybody's been quietly demoted back to Opus 4.8."
Culminates the immediate consequence of the government action.
"This is the first time in history a major AI company has pulled a live public model off the shelf because the federal government said so."
Stresses the historic nature of the event and its regulatory implications.

Questions This Video Answers

  • How does Fable 5 differ from Mythos 5 in terms of safety features and accessibility?
  • What exactly is an export control directive and how does it affect AI models like Fable and Mythos?
  • Who is Plenty the Liberator and what was the nature of the jailbreak claim?
  • Could Mistl or other competitors change the AI safety and market dynamics after Anthropic's move?
  • What are the potential long-term implications of government regulation on private AI deployments and IPO plans?
Fable 5Mythos 5Claude FableOpus 4.8Glass WingAnthropicPlenty the Liberatorexport control directiveHoward LutnikAI safety governance
Full Transcript
Over the weekend, something crazy happened. Just three days after the release of Claude Fable, the US government stepped in and curb stomped it in the name of national security. And that's bad news if you just FOMO subscribe to Claude Pro to try out Fable because now you'll see this disappointing message if you try to use it and instead be forced to use the negative IQ Opus 4.8. But it's all for your own good because it only took someone a few hours to jailbreak Fable and turn it into an unstoppable cyber weapon. And that's pretty ironic because here in the land of the free, an American company that will not stop talking about AI safety just got safetied by its own government. In today's video, we'll find out how and why our dear leaders in government are keeping us safe from the horrors of linear algebra. It is June 15th, 2026, and you're watching the code report. About 2 months ago on April 7th, we were first introduced to Mythos 5, the raw, unmuzzled model with the strongest cyber security capabilities of anything out there. But it was locked behind a program called Glass Wing, only available to trusted partners like major corporations and the US government itself. The reason Mythos can't be given to normies though is because it could easily be used as a cyber weapon in the wrong hands. To prevent that, Anthropic created a different product called Fable 5, which is literally the same exact model, but with safety classifiers bolted on. That means if you ask it to do bad things, like create an MPM package that turns the banking system into a Minecraft server, Fable's guardrails will reroute your request to Opus 4.8 before a dumber, more wholesome response. So basically, Mythos and Fable have the same brain, but Fable has a child lock on it. Fable went public and gained hundreds of millions of users overnight, and it was awesome. It was by far the best coding AI model I've ever used, and people were building all sorts of crazy apps with it. Life was good for about 3 days. Then, of course, an anonymous internet user who goes by Plenty the Liberator that defeats the guard rails and jailbreaks it. He's basically the internet's let's see if I can penetrate this thing guy and is famous for breaking other AI systems. And on June 10th, he post a jailbreak on X claiming he popped Fable's guardrails wide open and got it producing exactly the same stuff the Child Lock was built to block. And that's despite the fact that Anthropic had spent thousands of hours redeeming and trying to break its own guardrails internally. But the jailbreak wasn't some kind of sci-fi exploit. It actually works a lot more like moneyaundering. If Fable has a safety classifier watching for bad requests, but you can break dirty requests down into smaller innocent looking fragments by wrapping them in weird unicode characters by doing role-play farming or by confusing the model in a very large context conversation due to national security. I can't be any more specific than that. But this weakness was brought to Anthropic's attention and they were initially asked to take the model down, but they refused. Then on Friday at 5:21 p.m. Eastern time, Anthropic gets a letter not from a customer, but from the United States government. This letter was an export control directive signed off by Commerce Secretary Howard Lutnik. And the order was that no foreign national may access Fable 5 or Mythos 5. Not abroad, not in the US, and not even Anthropic's own foreignb born employees are allowed to touch it. That last one is pretty crazy that the government told a company that some of its own staff are no longer allowed to use the product they built. That means guys like Andre Karpathy, who just recently got the job at Anthropic, it can't even use Fable. In response to that directive, they decided to hit the big red button and yanked Fable and Mythos for everybody. And now everybody's been quietly demoted back to Opus 4.8. And this is the first time in history a major AI company has pulled a live public model off the shelf because the federal government said so. Many developers out there are not too happy with Anthropic right now. Because on top of this whole situation, there was already backlash over reports that Anthropic was intentionally degrading Mythos and Fable Performance on certain AI research jobs without making it obvious to users. But others out there are speculating that this whole thing was a calculated publicity stunt to continue pumping up Anthropic's preipo numbers while simultaneously building a regulatory moat around it. But I think the only thing that can truly stop Anthropic at this point is a better model from a competitor. A leaked benchmark shows that Mistl might have that model, but we're also awaiting new releases from Open AI and Google. Most of what we hear about AI is either non-stop hype from big tech or AI doomers warning us that the saw apocalypse will destroy the human race. But if you want to actually understand AI issues, you should check out Blue Dot. Impact, the sponsor of today's video. They're a nonprofit whose mission is to get more people involved in making AI go better for humanity. The main way they do that is by offering free online courses like their future of AI course, which provides an unbiased introduction to where AI is today and where things could be heading over the next few years. They also have more technical courses on things like AI governance and biocurity along with personalized career support for people interested in working on AI safety. All of Blue Dot's resources are free to use because they're funded by philanthropic donations and they've helped over 8,000 people get jobs at organizations like Google DeepMind, Stanford HAI, and Apollo Research to try out their future of AI course at the link below. This has been the code report. Thanks for watching and I will see you in the next one.

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