Harmonic Security Raises $50M Series B to Secure Enterprise AI Adoption

Harmonic Security, a workforce AI security platform, announced on October 14 that it has raised $50 million in a Series B round led by Crosspoint Capital Partners, with participation from existing investors. The round brings the company's total funding to $76 million. Harmonic Security plans to use the proceeds to expand its engineering and go-to-market teams in the United States and the United Kingdom.

The company said it currently protects AI use for millions of employees at more than 100 companies, including some of the world's largest enterprises. It also signed new distribution partnerships with Climb and Distology. Harmonic Security has grown to more than 90 employees across the US and UK.

The platform classifies AI tasks, identifies why they are used, and applies real-time controls. Over the past 12 months, it extended beyond browser-based AI monitoring to cover desktop AI tools and agentic workflows in a single platform. Harmonic's approach relies on custom small language models that read each interaction in context, which the company says helps security teams understand emerging use cases and allows business leaders to see which AI use cases create value. The company also noted integrations with Cisco Cloud Control's Agent Builder and Anthropic's Claude Compliance API.