Horizon3 has raised US$250 million in a Series E funding round at a valuation of more than US$2 billion, according to a company announcement. The round was described as oversubscribed and was co-led by existing investors NightDragon and NEA, with participation from seven new investors and five returning backers.
The company said the funding will support go-to-market scaling, international expansion and product development, as it positions its platform around autonomous security validation in response to AI-enabled cyber threats.
Horizon3 said the Series E follows its Series D valuation of US$650 million “in just over a year”. It also said its approach has contributed to 120% year-over-year ARR growth and that it now supports more than 7,000 organisations globally, including large banks, healthcare networks and four Fortune 10 enterprises.
The company’s NodeZero platform is marketed as an autonomous pentesting capability designed to test an organisation’s production environment to identify attack paths, provide remediation guidance and verify fixes. Horizon3 also said the platform can deploy honeypots during testing.
“We invented the concept of AI Hackers and spent six years earning the right to autonomously pentest the most critical and sensitive networks in the world — with no humans in the loop,” said Snehal Antani, co-founder and CEO of Horizon3. “Our massive data moat – built on 310,000 tests safely executed in production – combined with thousands of radical champions who love our product, has allowed us to achieve consistent top-tier financial and operational metrics. This round gives us the fuel to scale aggressively as the definitive leader of the AI vs. AI era.”
New investors named in the announcement include Acrew, Blue Cloud Ventures, EDBI, Demeter Group, PSG, SAIC and Sapphire. Returning investors listed include Craft Ventures, Prosperity7 Ventures, Qualcomm Ventures, Ridge Ventures and SignalFire.
As part of the investment, Dave DeWalt, founder and CEO of NightDragon and former CEO of FireEye and McAfee, and Morgan Kyauk, managing director at NightDragon, will join Horizon3’s board, the company said.
“Horizon3 coined the concept of cyber warfare being AI vs. AI, and that future has arrived,” DeWalt said. “Snehal and his team have built an unparalleled proactive security platform that is fundamentally reshaping how the world defends its data. I am thrilled to join the board to help Horizon3 secure the world’s most critical infrastructure and enterprises at scale.”
Internationally, Horizon3 said it plans strategic entry into Singapore and Australia, alongside deepening presence across EMEA. “This is a major milestone for Horizon3 in the region. It will help accelerate our growth across key markets, build critical regional skills, expand local teams in Australia, Singapore and Japan, and strengthen our presence on the ground,” said Gareth Cox, vice president of sales, APJ, Horizon3.
In Singapore, Yeung Chia Li, senior partner at EDBI, said Horizon3’s plans include establishing an ASEAN headquarters and a regional centre of excellence in Singapore.
On product development, Horizon3 said it will accelerate its roadmap to build what it described as “continuous learning” between AI attackers and defenders, including autonomous blue-team agents intended to remediate findings from NodeZero tests.
“It has never been harder for CIOs and CISOs. Attackers are getting faster, enterprise IT is becoming more complex, and regulators and cyber insurers are becoming more punitive,” Antani said. “We’re about to see an explosion of vulnerabilities, most of which won’t matter, but a small percentage will be immediately exploitable. The goal of running pentests isn’t to find problems, it’s to quickly fix exploitable problems that matter. We started with pentesting, evolved to be a proactive security platform, and will now accelerate remediation by creating AI learning loops between attackers and defenders.”
