Harmonic Security lands $50M Series B to police employee AI use
What's the deal? Harmonic Security raised a $50 million Series B led by Crosspoint Capital PartnersDealroom has a profile for this one. Try Dealroom →, bringing total funding to $76 million. The San Francisco- and London-based company said the round was oversubscribed and included existing investors, but did not disclose names or a valuation.
What's the endgame? Harmonic's software monitors how employees use AI tools and applies real-time controls. Rather than block AI outright, it lets security teams see which tools staff use, what data they share, and why.
How it works: The company says custom small language models examine each interaction within milliseconds, distinguishing a developer referencing a schema from someone copying live credentials. A Usage Intelligence layer helps managers spot valuable AI use cases and plan future investments.
Chief executive and co-founder Alastair Paterson said, "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."
The track record: Paterson previously co-founded threat-intelligence firm Digital Shadows, which sold to ReliaQuest for $160 million in 2022. Co-founder and chief technology officer Bryan Woolgar-O'Neil also came from Digital Shadows, along with the data and machine learning team.
By the numbers: Harmonic says its software reaches millions of employees across more than 100 companies. Its team has grown from 30 people in October 2024 to over 90 across the US and UK, and the new funding targets engineering, sales, and marketing in both regions.
Crosspoint managing director Zach Sivertson said, "As organizations embrace AI, they shouldn't have to choose between moving quickly and maintaining control."
Why now? The round lands as two rivals, Prompt Security and Aim Security, were acquired by larger security companies. Earlier backers include Next47Dealroom has a profile for this one. Try Dealroom →, which led a $17.5 million Series A in October 2024, and Ten Eleven VenturesDealroom has a profile for this one. Try Dealroom →, which led a $7 million seed.
The signal: At $50 million, Harmonic's round sits in the upper tier of recent raises, a sign of investor appetite for tools that govern enterprise AI without stopping it. With Anthropic building out compliance integrations across 100-plus security partners, controlling how employees use AI is fast becoming its own market.
Read more: Tech Funding News
Image credit: Harmonic Security
