Global Anthropic Ban Prompts Launch of Fugu and Tulongfeng

On June 27, 2026, Sakana AI and 360 Security launched new AI systems to replace Anthropic’s flagship models, following a two-week U.S. export ban on Claude Fable 5 and Mythos 5. The emergency directive barred foreign nationals from accessing Anthropic’s newest models due to national security risks. This hard cutoff forced developers outside the United States to immediately seek local alternatives for frontier workloads.

The Anthropic Supply Gap

On June 12, the Trump administration ordered Anthropic to pull Fable 5 and Mythos 5 offline globally because the company could not verify user nationalities in real-time. The U.S. government eased the restriction on June 26, allowing approximately 100 trusted U.S. organizations managing critical infrastructure to restore access to Mythos 5. For the rest of the world, the export directive remains in full effect.

Compliance concerns have already shifted corporate behavior. Major financial institutions in Hong Kong, including JPMorgan Chase and Goldman Sachs, disabled access to all frontier U.S. models to avoid violating strict interpretations of the export rules.

Before the ban, the Mythos-class models established a distinct performance tier above Claude Opus. The high pricing reflected this capability jump, with Mythos 5 costing $10 per million input tokens and $50 per million output tokens.

Benchmark	Mythos 5 / Fable 5	Opus 4.8
SWE-Bench Pro	80.3%	69.2%
FrontierCode (Diamond Split)	29.3%	~14.6%
CursorBench 3.1	72.9%	Not specified

Autonomous offensive cyber capabilities, including the ability to discover zero-day vulnerabilities in browsers and operating systems, directly triggered the federal intervention.

Asian Model Launches

Tokyo-based Sakana AI released Fugu, an orchestration model named after the Japanese blowfish and built on a 7-billion-parameter architecture. Instead of processing complex tasks inside a single massive neural network, Fugu uses a unified API to coordinate multiple external models and AI agents. Sakana claims this architecture matches Fable 5 on key benchmarks, marketing the system explicitly as a way to access frontier capabilities without export risk. For teams evaluating multi-agent coordination, Fugu offers a structural alternative to monolithic models.

Beijing-based 360 Security introduced Tulongfeng, a vulnerability discovery tool positioned as a direct replacement for the cybersecurity-focused Mythos series. Alongside it, the company launched Yitianzhen, an automated cyber defense system. These specialized tools target the exact autonomous security capabilities that the U.S. government sought to contain.

These late-June releases follow Zhipu AI’s launch of GLM-5.2, which debuted just one day after the initial Anthropic directive. Developers have increasingly adopted GLM-5.2 as an open-weight coding assistant due to its top-three global benchmark ranking and low operational costs. Industry analysts have hailed the release as a “DeepSeek moment” for the Chinese AI sector, proving that local labs can rapidly deploy cost-effective models that rival Western flagships.

If you run production workloads on frontier U.S. models, geopolitical availability is now a hard infrastructure constraint. You must design your routing layers to fail over to local or open-weight models when API access is suddenly revoked.