Harmonic Security has raised an oversubscribed $50 million Series B funding round led by Crosspoint Capital Partners, bringing the workforce AI security company’s total funding to $76 million. Existing investors also participated in the financing. Harmonic plans to use the new capital to accelerate growth, expand its engineering and go-to-market organizations in the United States and United Kingdom, and continue developing technology for securing enterprise use of artificial intelligence.
The company has grown to more than 90 employees across the U.S. and U.K. and said its platform now protects and enables AI usage for millions of employees across more than 100 companies. Harmonic has also signed new distribution partnerships with Climb and Distology.
Harmonic’s platform is designed to classify AI tasks, determine how employees are using AI applications, and apply controls in real time. Over the past year, the company has expanded beyond browser-based AI monitoring to cover desktop AI applications and agentic workflows through a unified platform.
A central component of Harmonic’s technology is its proprietary small language models, which analyze individual AI interactions in context. The company said this approach can distinguish between legitimate business activities and potentially sensitive behavior, such as a developer referencing a data schema compared with an employee submitting live credentials.
The same technology supports Harmonic’s Usage Intelligence capabilities, which are designed to show business and security leaders which AI applications and workflows employees are using, where AI is generating productivity benefits, and where additional controls may be appropriate.
Harmonic is also expanding integrations with major enterprise AI ecosystems. The company is an ecosystem integration for Cisco Cloud Control’s Agent Builder through Model Context Protocol technology. Separately, Harmonic has built an integration with Anthropic’s Claude Compliance API, providing security teams with visibility into Claude Platform activity logs and, for organizations using Claude Enterprise, conversation content across Anthropic-hosted deployments.
The Series B will support Harmonic as it expands its platform to address the growing use of generative and agentic AI throughout enterprise environments while giving organizations tools to manage data exposure and other security risks.
KEY QUOTES:
“Every board I talk to is asking two questions: how do we reduce the risk of AI use, and are we getting value? Most vendors struggle to answer the first, yet we address both. From the very start, we doubled-down on our custom small language models, which means we can benefit from a unique insight into enterprise AI use.”
Alastair Paterson, CEO And Co-Founder Of Harmonic Security
“Security has too often slowed the adoption of new technology. As organizations embrace AI, they shouldn’t have to choose between moving quickly and maintaining control. Harmonic gives leaders the visibility and confidence to accelerate adoption, while empowering employees to use the tools that make them more productive, all with the right guardrails in place. We’re proud to partner with Alastair and the Harmonic team.”
Zach Sivertson, Managing Director Of Crosspoint Capital Partners
“We’ve got some real momentum, and I know we’re just getting started. This round means we get to build that out faster and continue rapidly responding to the AI landscape shifts.”
Alastair Paterson, CEO And Co-Founder Of Harmonic Security
