Lightmark is a deep-tech startup developing capture-layer authentication infrastructure for visual media. Its core innovation is a hardware beacon that broadcasts a dynamic, invisible optical signature into a physical space before recording begins. Every camera present in that space — regardless of make, model, or software — captures the signature as a natural consequence of being there, making it physically impossible for AI to fabricate or strip.

The platform's three-step process — Beacon, Capture, Verify — enables sub-second verification of any footage to establish where and when it was recorded, whether it has been altered, and by whom. Outputs are designed to meet legal admissibility standards, supported by formal legal opinions from Clifford Chance and HGF. A UK patent application covering 15 core claims has been filed.

Lightmark's primary markets include Defence & Intelligence (battlefield footage, surveillance feeds, intelligence assets requiring chain-of-custody provenance) and media/broadcast compliance (targeting the EU AI Act Article 50 mandate requiring verified content authentication by August 2026). Development has been backed by Danish venture studio Bifrost Defence, and Lightmark has been selected by Innovate UK for its Global Growth Programme. The company is currently raising approximately £1.5 million to move from prototype to early commercial deployments.