Cosine Wins UK Backing to Build Sovereign AI Model

Sovereign AI is aimed at keeping model training, deployment and data governance under domestic control, a priority for defence, finance and critical infrastructure where sensitive information cannot be sent to foreign-hosted systems. London-based Cosine is trying to turn that policy into a product with Lumen Sovereign, a frontier model built by a team of about 30. The effort matters because Britain remains dependent on US providers such as OpenAI and Anthropic, while Cosine must compete with companies that command far greater capital, computing capacity and talent.

The Department for Science, Innovation and Technology’s Sovereign AI Unit named Cosine among its first supported startups on April 16, 2026. The £500 million programme awarded access to the Isambard-AI supercomputer in Bristol, though no company-specific cash amount was disclosed. On June 8, Cosine said BT, Lloyds Banking Group, BAE Systems and other institutions would help co-design Lumen Sovereign, a roughly 1.35 trillion-parameter mixture-of-experts model. Training is to take place entirely in Britain, with deployment readiness, including for air-gapped systems, targeted by the end of 2026.