Gray Swan Closes $40M Series A to Stress-Test AI Models

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Gray Swan, an AI security startup based in Pittsburgh, has closed a $40 million Series A. Wing Venture Capital and Madrona co-led the round, with participation from Obvious Ventures, Snowflake Ventures, Hudson River Trading, Samsung Next, and returning investor Magarac Venture Partners.

The company is a Carnegie Mellon University spinout. It builds tools that safety-test AI models and agents for vulnerabilities, and its work has shown up in reports from major firms including Anthropic, OpenAI, and Meta. Founders Matt Fredrikson and Zico Kolter spent more than a decade studying how AI systems break down under adversarial pressure and how to head off those failures.

Gray Swan plans to put the funding toward speeding up its go-to-market work, deepening its relationships with frontier labs, and growing its team.

The company is currently working with more than 20 customers spanning frontier labs and global enterprises. It had previously raised $5 million in early-stage capital in 2024, followed by another $5 million in 2025.