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Crosslayer Labs

Crosslayer Labs

Winter 2026

Protect, monitor and defend your Internet presence

San Francisco, CA, USA20263 peopleActive
SaaSB2BCybersecurity
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About Company

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.

Active Founders

Henry Birge-Lee

Henry Birge-Lee

Founder

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.

Grace Cimaszewski

Grace Cimaszewski

Founder

I'm a soon-graduating PhD student at Princeton. 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.

Prateek Mittal

Prateek Mittal

Founder

I am a professor at Princeton University and co-founder of Crosslayer Labs (YC W26). I'm broadly interested in cybersecurity and privacy. 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).

Company Facts

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workspace_premiumBatchWinter 2026
groupTeam Size3
calendar_monthFounded2026
trending_upStageEarly
categoryIndustryB2B
location_onLocationSan Francisco, CA, USA
boltStatusActive
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