The Engineer Who Keeps Coming Back
He already had the exit. The acquisition by KnowBe4 in October 2021 closed. SecurityAdvisor - the company he co-founded that helped create an entirely new category called Human Detection and Response - belonged to someone else now. Santhosh Purathepparambil could have stopped there. He didn't. Within two years, he was building again.
That is the pattern with Santhosh. Not the comfortable arc - sell, consult, angel invest, repeat. Something harder. He looks at enterprise security and keeps finding the same structural problem from a new angle: organizations spend enormous sums on security tools, but those tools don't talk to each other, don't align on policy, and leave CISOs staring at a stack of dashboards that contradict each other. The money flows in. The risk stays.
His training runs deep. Stanford's School of Engineering. Years at McAfee as Senior Director of Engineering, inside one of the most complex security stacks ever built for enterprise. That's where you learn what "scale" actually means - not pitch-deck scale, but the kind where a misconfiguration at 3 a.m. touches millions of endpoints before anyone wakes up. The lesson wasn't how to sell security software. It was how brutally hard it is to run it.
The cybersecurity landscape demands perpetual innovation and fine-tuning.
- Santhosh Purathepparambil, Co-Founder, Discern SecurityWhen he co-founded SecurityAdvisor alongside Sai Venkataraman and Rohan Puri, the bet was on human behavior as the attack surface. That turned out to be right. KnowBe4 agreed enough to buy the company. But the next problem Santhosh spotted was more technical, more systemic - and arguably bigger. Not the people clicking phishing links. The tools themselves. Misconfigured, fragmented, expensive, and largely pointing in different directions.
So in January 2023, the same three founders - Venkataraman, Purathepparambil, and Puri - sat down again. Same founding team. Different problem. Discern Security was born.
Five AI Agents. One Coherent Security Strategy.
As Chief AI Scientist, Santhosh designed the AI layer that makes Discern Security's platform run. Not a chatbot bolted onto existing software. An agentic architecture where distinct AI agents take on distinct jobs, working continuously in the background while the security team focuses on decisions rather than maintenance.
Atlas converts security questions into dashboards and queries - the part of the job that usually consumes analyst time. Oracle provides the contextual layer: what does this anomaly mean given this specific organization's profile? Pathfinder prioritizes what to fix first. Resolve tracks the fixes. Mesh keeps security policies aligned across tools in real time.
Together they form what Discern calls a "Policy Intelligence Hub" - a live map of an organization's security posture that doesn't just report what's happening but acts on it. Discover. Assess. Remediate. At machine speed. The platform earned SOC 2 and ISO 27001 certifications, which matters when you're asking Fortune 500 companies to let AI agents touch their security configurations.
From McAfee Engineering to AI-Native Security
What the Repeat Founder Knows That First-Timers Don't
Most cybersecurity companies get founded by CISOs or ex-government people who understand threats. Santhosh comes from the other side - the engineering side, the side that has to implement all those threat frameworks against the reality of 40 different security tools with conflicting configurations. That perspective is rare.
At McAfee, he watched enterprise security from inside the machine. At SecurityAdvisor, he watched it from the human-risk angle. At Discern, he's looking at the layer underneath both: policy. The gap between what an organization's security policy says should happen and what's actually configured across their tools. That gap costs money. It creates risk. And until AI, there was no cost-effective way to close it continuously.
The founding team raised $3M from investors who have seen this pattern before. BoldCap, WestWave Capital, Cyber Mentor Fund, and Security Syndicate didn't just back a product - they backed a team that had already proven they could build, sell, and exit in cybersecurity. The CISOs who co-invested know the problem from the other side: they're the ones whose budgets get wasted when tools don't align.
The Scorecard
What's New at Discern
Facts Worth Knowing
- 01 His company's AI agents have names drawn from mythology and exploration: Atlas holds the sky, Oracle sees what others can't, Pathfinder navigates terrain, Resolve follows through, and Mesh connects everything.
- 02 He co-founded two separate cybersecurity companies with the exact same founding team - Sai Venkataraman and Rohan Puri. That kind of repeat partnership is rare, and it shows.
- 03 Discern Security's baseline security audits regularly surprise enterprise clients by revealing more assets - and more inefficiencies - than the clients knew they had. The gap between "believed" and "actual" is the product.
- 04 His career spans two distinct eras of enterprise security: the rule-based, signature-driven McAfee era and the AI-native era he is now helping define at Discern Security.