Harmonic Security Raises $50M to Govern Employee AI Tool Usage

Series B Round Led by Crosspoint Capital

Workplace artificial intelligence security startup Harmonic Security Inc. announced October 14 that it has raised $50 million in new funding to grow its platform for governing how employees use AI tools. The oversubscribed Series B round was led by Crosspoint Capital Partners LP, with existing investors also participating. It follows the company's $17.5 million Series A round led by Next47 in October 2024, bringing total investor funding to $76 million.

The company said the new capital will pay for additional engineering and go-to-market hires across the United States and the United Kingdom, where staff numbers have already passed 90.

How the Platform Works

Harmonic's platform inspects anything an employee sends to an AI tool at work before it gets there. Custom small language models read each interaction in context and return a verdict within milliseconds. According to the company, live credentials pasted into a chat window are one example of what the system is tuned to catch, while a developer referencing a database schema should pass.

Those checks originally ran only in the browser. Over the past year, Harmonic has extended them to desktop AI applications and agentic workflows, which in the company's view are where problems such as employees signing in to AI services with personal accounts tend to start.

Co-founder and Chief Executive Alastair Paterson said every board he talks to now wants to know whether AI is delivering value, on top of how to reduce the risk of using it. Harmonic's answer is a Usage Intelligence layer that runs on the same models, giving leaders visibility into which AI use cases are paying off, down to individual employees who have found a faster way to get their jobs done.

Integrations and Customer Growth

Harmonic has been plugging into tools enterprises already use. Agent Builder, which Cisco Systems Inc. announced for its Cloud Control platform at Cisco Live in June, lists Harmonic among its ecosystem integrations, with the connection running over Model Context Protocol. A second integration with the Claude Compliance API from Anthropic PBC pulls activity logs from Anthropic-hosted Claude Platform deployments into Harmonic, and organizations on Claude Enterprise also receive the content of conversations.

More than 100 companies are customers, some of them among the largest enterprises in the world, and Harmonic said millions of their employees are covered. Climb Global Solutions Inc. and Distology Ltd. have signed on as distribution partners.

Zach Sivertson, a managing director at Crosspoint, said security has too often slowed the adoption of new technology, and that organizations taking up AI should not have to give up control to move quickly. Paterson said the company has real momentum and that the round lets it build faster as the AI market keeps changing.

Sources: SiliconANGLE · Techmeme