Gray Swan
Frontier-lab red teaming (Shade) and runtime defense (Cygnal) trained on unpublished attacks.
Proof of life. Raised $40M Series A co-led by Wing and Madrona, May 2026
About Gray Swan
Gray Swan came out of Carnegie Mellon adversarial ML research and sells the same threat intel that labs use before a model ships. Shade runs LLM-based attackers against your model, guardrails, and tool wiring.
Cygnal is the production classifier trained on those attacks, including findings from a public Arena of thousands of researchers, so defenses track the frontier instead of last year's jailbreak list.
Investors
Wing Venture CapitalMadronaObvious VenturesSnowflake Ventures
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