Analysis
Horizon3 closed a $250 million Series E on Monday at a valuation topping $2 billion, tripling its mark from the $650 million it carried at its Series D just over a year ago. The round was co-led by existing investors NightDragon and NEA, with seven new investors joining five returning backers -- an oversubscribed raise that Horizon3 says reflects the same AI-versus-AI dynamic reshaping cybersecurity budgets industry-wide.
NodeZero's Pitch: Attack Yourself First
The company's product, NodeZero, is marketed as an autonomous 'AI Hacker' that continuously tests a customer's own production network for the same misconfigurations, weak credentials and identity gaps a real attacker would chain together -- then verifies each fix by rerunning the attack path. That continuous, autonomous-pentesting model has powered 120% year-over-year ARR growth, and Horizon3 now says it protects more than 7,000 organizations globally, up sharply from its customer base at Series D.
Horizon3 plans to use the new capital to expand sales, marketing and channel operations across enterprise, mid-market and federal customers, and to open offices in Singapore and Australia while deepening its presence across Europe, the Middle East and Africa -- an international expansion that mirrors how quickly AI-native security spending is globalizing beyond its initial US enterprise base.
What to watch: whether Horizon3's international offices convert into meaningful non-US revenue within the next two quarters, and whether the broader 'autonomous pentesting' category consolidates around Horizon3 or fragments as more AI-native security challengers raise their own mega-rounds.
