Anthropic invites 150 more organizations to Claude Mythos preview, citing cybersecurity risks

Anthropic has invited approximately 150 additional organizations to Project Glasswing, its restricted preview program for Claude Mythos, the frontier model announced in April 2026 that remains unavailable to the public.

The new invitees span more than 15 countries and include public utilities (power, water, telecom) and healthcare providers—sectors underrepresented in the original cohort of nearly 50 partners that included Apple, Amazon, Broadcom, CrowdStrike, Microsoft, and NVIDIA.

Why Mythos remains restricted

Anthropic formed Project Glasswing specifically to control access to Claude Mythos due to what the company describes as unprecedented coding capabilities. "AI models have reached a level of coding capability where they can surpass all but the most skilled humans at finding and exploiting software vulnerabilities," Anthropic stated.

Each organization must pass Anthropic's security requirements before receiving access. According to the company, "a successful attack on their codebase could be catastrophic," with most partners representing systems that could affect more than 100 million people.

Public release timeline unclear

Anthropic says it is working "as quickly as we can to safely release Mythos-level capabilities" but will not make the model widely available until it implements "highly robust safeguards" to prevent misuse of its cyber capabilities. The company has not provided a specific timeline.

No technical specifications for Claude Mythos have been disclosed, including context window size, parameter count, or pricing.

Regulatory implications

In May 2026, the Claude Mythos announcement reportedly prompted the Trump administration to consider an executive order establishing a process for the federal government to share AI-identified software vulnerabilities with critical institutions before models became publicly available. The signing ceremony was postponed due to objections from the president and the tech industry, according to reports at the time.

What this means

The expansion of Project Glasswing to 200 total organizations while maintaining restricted access suggests Anthropic views the security risks as significant enough to justify an indefinite delay in public release—an unprecedented move for a frontier model from a major AI lab. The lack of disclosed technical specifications or benchmarks makes it impossible to verify the model's claimed capabilities independently. If Anthropic's assessment is accurate, this represents the first AI model where offensive security capabilities have explicitly prevented a standard commercial release.