Joint London and San Francisco-based Harmonic Security has secured $17.5M in Series A funding to bring its “zero-touch data protection” capabilities to enterprises. Total funding has now reached more than $26M since the company launched in October last year with enterprise customers already in double figures. 

Harmonic already employs 30 people across the United States and the United Kingdom, and will use this latest round of funding to scale up its engineering and go-to-market efforts. 

Harmonic Security’s approach to data protection uses pre-trained, specialized language models. The Series A round is being led by Next47, a leading venture capital firm that has invested in many cybersecurity standouts, including Claroty and Sysdig. It joins Ten Eleven Ventures which led the $7M seed round in October 2023. 

Alastair Paterson, CEO and co-founder of Harmonic Security comments: “Over the past 20 years, complex data classification and labeling exercises and noisy rules have created headaches for security teams, not least a huge burden of meaningless false positives. Now, with the rapid adoption of Generative AI, renewed data privacy risks mean that legacy data protection tools are not fit for purpose. Harmonic Security is redefining the entire data protection category which GenAI has brought into sharp focus and we will use the Series A to accelerate the rapid progress we have already achieved.” 

“Next47 is thrilled to join Harmonic Security on its mission to reimagine data protection for the modern age,” said T.J. Rylander, General Partner at Next47, who will join the company’s board. “As we move towards the concept of the AI-powered SOC, Harmonic will own data protection for the GenAI era.” 

The company has trained its own language models for data protection that are based on unique datasets of highly realistic sensitive materials. This breakthrough allows Harmonic to accurately detect all types of sensitive data in milliseconds. The extreme accuracy and speed of this approach mean that it can nudge end users towards secure best practices without overwhelming security teams. 

One CISO leading the charge and getting behind Harmonic is Rinki Sethi, CISO of BILL: “Data security is long overdue disruption. What’s even better is that Harmonic has the team to bring this to life.”

Mark Sutton, CISO of Bain Capital, recently became a board member at Harmonic to help drive this mission: “Traditional Data Loss Prevention (DLP) methods have proven ineffective, leading CISOs to shift focus towards user authentication, authorization, and visibility. While specific types of data can be easily protected, the contextual nature of most sensitive information makes binary ‘yes or no’ controls inadequate, creating more operational friction than value.”

Harmonic’s close relationship with CISOs has enabled quick traction after launching its data protection product in July 2024 which is active use by thousands of employees. As a result, it has generated significant attention in 2024, including being named an RSA Innovation Sandbox finalist.