In the AI era, attackers are becoming master manipulators — deploying highly convincing deepfakes, real-time voice impersonations, SMS phishing attacks, and contextual social engineering.
The human layer is now the most actively targeted and most difficult to defend. Despite billions spent on tools and training, human error remains the #1 cause of breaches.
To meet this challenge, we’re proud to introduce Fable Security—a company initiated through Greylock Edge and launching with $31M in financing, including a $6.5M Series Seed financing led by Greylock Partners and a $24.5M Series A financing led by our friends at Redpoint Ventures. Fable’s AI-native platform transforms human risk from an open vulnerability into a dynamic line of defense.
Fable’s platform continuously monitors behavioral risk signals—like suspicious file sharing, risky clicks, or unusual access patterns—and delivers context-aware, AI-generated interventions that nudge users toward safer behavior. These interventions span Slack nudges, embedded video explainers, just-in-time risk workflows, and conversational coaching—all personalized to the user’s role, risk profile, and context. It’s a closed-loop feedback system for shaping safer decisions without friction. Enterprise customers are already seeing measurable improvements: 85% fewer phishing clicks, 60% drop in accidental data exposure, and consistent behavior change within hours.
Nicole Jiang (CEO) and Sanny Liao (CPO) are world-class founders who bring deep operational and technical experience. Nicole helped lead design and product management at Abnormal AI, and Sanny built adaptive learning systems at both Abnormal AI and TellApart. Their shared insight—that legacy training cannot match attacker velocity—drives every aspect of Fable’s product design. They’ve built a team that blends security acumen, AI, and behavioral psychology, with early hires from Google, Stripe, Rippling and other leading technology companies.
At Greylock, we have been privileged to partner early and initiate companies with outlier entrepreneurs in markets where we have expertise, including companies like Palo Alto Networks, Workday, Abnormal AI, Sumo Logic, TellApart, and Obsidian Security. Fable extends that tradition: an exceptional team tackling a massive market with a category-defining vision for human risk management.
We’re excited to support the Fable team as they build the system that helps humans become security’s strongest link.
