Cosine

Founded in 2022 by Alistair Pullen (CEO) and Yang Li (COO), both Cambridge PhDs, Cosine was named cornerstone investee of the UK Sovereign AI Fund on 16 April 2026, receiving 500,000 GPU hours on Isambard-AI and an option for follow-on equity in its next funding round .

Cosine builds the only end-to-end air-gapped sovereign AI coding system built, owned, and operated entirely within Britain. Its system supports 38 programming languages including Fortran and COBOL, targets nuclear, defence, and financial-services clients, and runs entirely on-premise with no internet connections or foreign model dependencies. It has outperformed OpenAI, Anthropic, Mistral AI, and DeepSeek on independent coding benchmarks for two consecutive years.

Cosine's selection by DSIT signals that the UK sovereign AI strategy is tilting toward regulated and defence applications rather than general-purpose AI. COO Yang Li framing — the UK should be an AI maker, not an AI taker — positions the company as the counterpoint to OpenAI's simultaneous opening of a permanent London office. The Sovereign AI Fund's option to follow on in Cosine's next round makes it effectively a cornerstone holding of Britain's national AI portfolio .