Job Title: Defence Account DirectorLocation: London; full in-office working as defaultStart date: ASAPReports to: CCOCompensation: Salary and Equity options available for discussionClearance: Must be eligible to hold UK Security Vetting Clearance SC or above (no prior clearance required)Application deadline: 01/11/26 at 23:59 UK time___________________________________________________________________________Help make sovereign AI operational for UK DefenceCosine is a UK AI lab building models, applications and infrastructure for mission-critical organisations.
We build coding agents, specialised Lumen models, AI-native security products and the infrastructure required to deploy advanced AI in demanding environments.
We are also training Lumen Sovereign, the first frontier large language model trained in the UK, with the support of the UK Government.
Defence is a strategic priority for Cosine.
AI will change how Defence operates, from software engineering and intelligence analysis to cyber security, command and control, logistics and frontline operations.
The challenge is turning advanced AI into capability that is trusted, secure, sovereign and useful in the real world.
We are looking for a Defence Account Director to help build that business.
This is not a traditional defence sales role.
You will understand where Cosine can make a genuine operational difference, identify the right customers and programmes, shape credible opportunities and help turn early conversations into funded pilots, programmes and long-term customer relationships.
You will work closely with Cosine’s Defence Lead, technical teams and senior leadership.
You will build relationships across the MOD, the Armed Forces, wider Government and the UK defence industry, while helping define Cosine’s position in the emerging sovereign AI market.
___________________________________________________________________________What you’ll doBuild and own a prioritised Defence account and opportunity strategy.