Harmonic Security
Harmonic Security provides software that discovers, classifies and controls how employees use AI tools at work.
- Categories
- AI and LLM security, Data loss prevention, SaaS security, Endpoint protection and antivirus
- Based in
- San Francisco, United States
- Founded
- 2023
- Ownership
- Private
- Certifications
- ISO/IEC 27001, SOC 2 Type 2, ISO/IEC 42001
About Harmonic Security
Harmonic Security sells an AI governance and control platform. It helps security teams see how staff and AI agents use AI tools, then apply controls in real time. The platform collects activity at the source, sorts it by business use case, and acts on it so security decisions follow the work rather than blocking it. The company says its difference is context. Small language models read each interaction and judge intent in under 200 milliseconds, so it can govern inline where pattern-matching DLP can only monitor. It covers browser, endpoint and MCP surfaces, including desktop apps, embedded AI and autonomous agents. Deployment takes minutes through Intune, JAMF, Kandji or Group Policy. It sells to security teams across technology, legal, insurance and healthcare. Buyers can block, warn or log, and configure the governance layer themselves.
Products
- Harmonic ExploreA live preview of the Harmonic console that can be explored without a signup.
- Harmonic GuideGives visibility into AI use and coaches employees in real time when sensitive data is about to be shared.
- Harmonic CommandAdds controls for humans and agents, including permissions on what agents may do across MCP servers.
- AI Application Detection and Response (AIDR)Detects and responds to AI applications in use across the organisation.
- Shadow AI Usage IntelligenceFinds and categorises unapproved AI tools and tracks adoption trends.
- Endpoint AI SecuritySecures AI use on employee devices.
Ownership and deals
- Raised $50m in a Series B roundInvestor Crosspoint Capital PartnersReport on the Harmonic Security funding round of 14 Oct 2026 (opens in a new tab)
- Raised $17.5m in a Series A roundInvestor Next47Report on the Harmonic Security funding round of October 2024 (opens in a new tab)
- Raised a seed roundInvestor In-Q-TelReport on the Harmonic Security funding round of May 2024 (opens in a new tab)
- Raised $7m in a seed roundInvestor Ten Eleven VenturesReport on the Harmonic Security funding round of October 2023 (opens in a new tab)
Acquisitions come from SecurityWeek's monthly M&A round-ups from 2021 onwards, from Cybersecurity Ventures' quarterly M&A reports for 2020, and a few from Wikipedia lists. Funding rounds from 2022 onwards come from Return on Security's weekly Security, Funded newsletter. These are dated to the month. A few deals added from the news are dated to the day. Smaller deals may be missing. Amounts are in US dollars.