As artificial intelligence agents increasingly interact with sensitive corporate systems at machine speed, enterprises face new security challenges. Venture capital firm Sequoia Capital has invested $30 million in Cymphony, a startup focused on securing AI agents alongside human employees within organizations. The funding round, which includes $25 million in Series A financing co-led by Sequoia and SMBC Fin Atlas Beyond Fund, values Cymphony at over $100 million. The company is based in New York and Tel Aviv and had previously received a seed investment from Sequoia.
AI agents often bypass traditional access and identity controls designed for human workers, yet they can access multiple systems and handle large volumes of sensitive data. This complexity makes it difficult for security teams to track and manage access effectively. Cymphony addresses this gap by providing a unified platform that offers visibility into employees, AI agents, and other non-human identities, along with the systems and data they can access.
At the heart of Cymphony’s solution is a "workforce graph" that integrates identity, data, and activity signals. This approach helps security teams monitor AI agents that operate independently but are increasingly part of the enterprise workforce. The startup has already identified significant exposures, such as one case where approximately 85,000 files were accessible to AI tools within a public U.S. company. Cymphony helped close the exposure and confirmed no unauthorized access occurred.
In another instance, an external collaborator deployed an unsanctioned AI agent using Anthropic’s Claude to scan thousands of sensitive files, highlighting the risks of unmanaged AI deployments. Beyond detection, Cymphony leverages AI to investigate incidents, prioritize security responses, and automate remediation tasks like adjusting access permissions. Customers can choose to use the platform autonomously or engage Cymphony’s experts for managed services.
Sequoia’s renewed investment reflects confidence in Cymphony’s progress since its seed round over two years ago, when the startup had no product or clear market focus. The founders’ backgrounds in Israel’s elite Talpiot military program initially attracted Sequoia’s interest. Since then, Cymphony has developed a product, secured over a dozen enterprise customers, and achieved seven-figure annual recurring revenue. Its client roster includes KKR, Syngenta, Cass Information Systems, and Athennian.
Sequoia partner Bogomil Balkansky noted that the firm has used Cymphony’s platform internally and values the startup’s ability to combine identity and data security, a distinction that sets it apart in a competitive market. As AI agents evolve, their dynamic behaviors and ability to create other agents complicate traditional security models designed for human users.
Cymphony competes with established cybersecurity companies expanding into AI and identity security, such as Microsoft, Okta, CyberArk, Wiz, and Varonis. The startup has already begun consolidating security tools for some customers, reducing the need for multiple point solutions. However, Sequoia views Cymphony’s current role as complementary rather than a replacement for existing identity platforms.
With around 30 employees across Tel Aviv and New York, Cymphony primarily serves North American enterprises but is seeing growing interest from Europe, the Middle East, and Africa. As the company scales, it aims to establish AI agent security as a distinct market segment rather than a feature within broader security platforms. Sequoia believes investment in this area will increase as enterprises deploy more AI agents in their operations.
"If companies are not spending money on agent security, I don’t know what else they’ll be spending money on in the next five to 10 years," Balkansky said, underscoring the strategic importance of this emerging security domain.