Security

Crosslayer Labs

Website

Crosslayer Labs detects impersonation attacks on websites and APIs. We provide "outside-in" monitoring of customer infrastructure, comprehensively discovering and monitoring all Internet dependencies, including DNS, BGP, TLS certs, Javascript. We correlate signals from different layers of the Internet stack to identify attack patterns. Our alerts a

Founded 2025Origin source ↗Checked 2026-09-15

Overview

Crosslayer Labs detects impersonation attacks on websites and APIs. We provide "outside-in" monitoring of customer infrastructure, comprehensively discovering and monitoring all Internet dependencies, including DNS, BGP, TLS certs, Javascript. We correlate signals from different layers of the Internet stack to identify attack patterns. Our alerts are actionable and contain root cause analysis/remediation recommendations. Our founding team is world renowned for previously inventing the MPIC standard adopted by all the major CAs including Google, Apple, Amazon. The MPIC standard is securing over 700 million websites via the issuance of over 3 billion digital certificates, and is now a global internet standard that protects every single HTTPS connection.

Company description As recorded 2026-11-08

Founders & team

Henry Birge-Lee

Founder/CEO

I am am innovator in web and network security. I invented Multi-Perspective Issuance Corroboration (MPIC) which now secures every single HTTPS connection. I am currently focusing on building the Crosslayer Labs platform for web resource integrity.

Founder profile As recorded 2026-09-15

Grace Cimaszewski

Founder/CTO

I'm a recent PhD graduate from Princeton and security researcher. I've worked with the CA/Browser Forum to turn my research on TLS certificate security into ecosystem-wide requirements which now improve the security of every HTTPS connection you view in your browser. Before starting Crosslayer with my long-time research collaborators, I was a visiting research at Google and Corelight Labs.

Founder profile As recorded 2026-09-15

Prateek Mittal

Founder

I am a professor at Princeton University and co-founder of Crosslayer Labs (YC W26). I specialize in the field of cybersecurity/privacy and am the recipient of the ACM Grace Hopper Award. My research has helped secure every single web connection (HTTPS) worldwide and enhanced the security of deployed LLMs (e.g., GPT 3.5 and GPT4V at OpenAI).

Founder profile As recorded 2026-09-15
3team members reported
Source-reported As recorded 2026-09-15

Founded 2025 · Source

News & product activity

Sources & observations

Y Combinator

Profile depthenriched profile
Website observationwebsite reachable
Last website check2026-11-11
Location · source statedNew York City, NY, USA
Pricing evidenceNo pricing page confirmed
Maturity: Not assessed · 3 of 6 areas documented

Source-based assessment · automated evidence rules

The retained text does not establish product availability or customer use.

Maturity is an evidence-based assessment, not a success rating. It may understate the current stage where evidence is limited. Coverage records documented areas, not a complete or independently audited company history.

Stage definitions
independent websitesource corroborationreachable websitedescriptive evidenceclassified market and modelsourced peoplesourced founding yearrecent publishing observed