Horizon3 Raises $250M Series E at $2B+ Valuation to Lead the “AI vs. AI” Cybersecurity Era

<p>SAN FRANCISCO — August 3, 2026 — Horizon3, the AI-Native Proactive Security Company behind NodeZero®, the World’s Best AI Hacker, today announced a $250 million Series E at a valuation of more than $2 billion, tripling its valuation from $650 million at Series D in just over a year. The oversubscribed round was co-led by existing investors NightDragon and NEA, with participation from seven new…