The U.S. government ordered Anthropic to shut down its two most capable AI models — Fable 5 and Mythos 5 — on Friday evening, citing national security authorities. The directive required the company to suspend all access to the models for any foreign national, both inside and outside the U.S., and then execute a full shutdown for all customers. The news sent Hyperliquid's synthetic cash-settled Anthropic perpetual futures down 3.7% to roughly $1,627 on Saturday.
Contract Had Traded Near All-Time Highs; Open Interest at $8.6M
Just days after Fable 5 launched, the Anthropic perp was hovering near all-time highs above $1,800. Current open interest stands at about $8.6 million — modest compared to SpaceX's perpetual but still meaningful for a company that hasn't filed an IPO yet. The market had priced in a strong listing narrative fueled by Anthropic's safety-first branding and advanced model performance.
Anthropic Disputes the Order, Calls the Jailbreak 'Narrow'
Anthropic said it received the verbal instruction from the government at 5:21 p.m. ET on Friday. Officials claimed they had identified a method to bypass, or jailbreak, Fable 5. After internal review, Anthropic characterized the technique as narrow — not a universal jailbreak — involving a small number of previously known, minor vulnerabilities. The company noted that other publicly available models, including OpenAI's GPT-5.5, can find those same vulnerabilities without any bypass. “Applying this standard across the industry would essentially halt all new model deployments for all frontier model providers,” Anthropic said in a statement. The firm, which built its brand on safety-first AI development, is now publicly pushing back against a national security directive, arguing that the government's evidence does not clear its own stated bar.
Market Prizing the Shutdown as a Negative for IPO Case
Crypto traders moved quickly: the pre-IPO perpetual dropped from its post-launch highs, reflecting the perception that the shutdown complicates the IPO timeline. Anthropic said it will release more details about the specific jailbreak within 24 hours. The key question now is whether the order will be reversed, narrowed, or extended to other model classes once Anthropic publishes its technical rebuttal.