Analysis
AI-agent security has become one of 2026's fastest-funded startup categories. Glow emerged from stealth with $180 million raised across three rounds in roughly a year, reaching a $1.2 billion valuation to rebuild endpoint security specifically for AI-native threats. Onyx Security raised $113 million just four months after its own stealth launch, reaching a roughly $640 million valuation for a platform that monitors and controls what autonomous AI agents actually do inside enterprise software.
The two companies are attacking related but distinct problems. Glow focuses on protecting the endpoint itself against AI-era threats; Onyx focuses on governing the behavior of AI agents running on top of enterprise systems once they're already inside. That the category is splitting into specialized layers this early -- rather than consolidating around a single platform -- suggests investors see enough surface area in "AI agent security" broadly to fund multiple distinct winners rather than betting on one.
“The two companies are attacking related but distinct problems.”
What's most notable is the speed: both companies reached nine- or ten-figure valuations within months of emerging, not years. That compression mirrors what's happened across most AI-native software categories in 2026, and reflects genuine enterprise urgency -- agent oversight barely existed as a budget line two years ago and is now attracting some of the fastest-moving capital in security. What to watch: whether Glow and Onyx end up competing head-to-head as their product surfaces expand, or whether the category stays cleanly segmented.
