Horizon3, a San Francisco-based AI-powered cybersecurity firm, has raised $250 million in Series E funding, bringing its valuation to more than $2 billion. The round, led by NightDragon and NEA with participation from existing and new global strategic investors, was oversubscribed. The company said the capital will fuel international expansion of its AI-native cybersecurity platform and accelerate innovation in proactive threat defense.
The new valuation more than triples the approximately $600 million valuation from its previous funding round. Horizon3 plans to use the investment to grow sales and marketing globally, expand its European presence, and enter Singapore and Australia. The company also intends to increase research spending on its NodeZero platform and autonomous AI security agents, which automatically identify and remediate vulnerabilities across enterprise IT environments.
NodeZero, founded by former JSOC colleagues Snehal Antani and Anthony Pillitiere, uses self-driving penetration testing technology to continuously attack customer networks and uncover security weaknesses. Unlike traditional annual assessments, the platform safely tests live production environments on an ongoing basis. Horizon3 says it has completed more than 310,000 production security tests across enterprise customers worldwide, evaluating entire infrastructures without interrupting operations. The platform also includes intelligent honeypots to detect active attackers in real time. More than 7,000 enterprises, including organizations in banking, Healthcare, government, and Fortune 10 companies, currently use the platform.
Enterprise demand for such capabilities is rising as AI-driven threats become more sophisticated. Horizon3 reported approximately 120% annual recurring revenue growth, approaching $100 million in ARR last year, and serves between 7,200 and 7,300 customers globally. The company said the funding will support development of AI learning loops that enable defensive systems to continuously improve by analyzing emerging attack techniques. This aims to shift enterprises from vulnerability awareness to automatic remediation of critical threats.
As cyber threats evolve at machine speed, Horizon3 asserts that AI-powered security testing is becoming indispensable for enterprises seeking to protect essential assets and proprietary data. The latest financing positions the company to meet growing global demand for autonomous, continuous cybersecurity solutions.
