British Business Bank backs UK-dedicated deeptech fund to support startups and early-stage innovators
The British Business Bank has announced a cornerstone commitment of up to £50m to Longwall Venture Partners LLP’s (‘’Longwall’’) latest fund, Longwall 4, to support start up and early-stage deeptech companies. The commitment is made through the Bank’s Enterprise Capital Funds programme.
The Bank has previously made commitments to Longwall, backing its Oxford Technology ECF LP (2008), Longwall Ventures ECF LP (2012) and Longwall Ventures 3 ECF LP (2017) funds. This latest commitment represents the fourth Longwall fund the Bank has backed.
Founded in 2008, Longwall Ventures is an established UK early-stage venture capital firm dedicated to deeptech companies. With over 18-years’ experience commercialising scientific research and breakthrough technologies into global businesses, it has invested in more than 50 companies ranging from medical devices to defence and aerospace applications.
Longwall’s first fund, Oxford Technology ECF LP (OTECF), was one of the first investors in OrganOx, which was sold in 2025 to Terumo Corporation for over $1.5bn – the largest acquisition of an Oxford University spinout to date and one of the UK’s biggest medtech exit deals – delivering a 19.2x return for investors including the Bank. With five exits so far in OTECF, the fund’s private LPs have received a return of 6x on their original investment to date.
The Bank’s Enterprise Capital Funds programme aims to increase the supply of equity capital to early-stage UK companies with long-term growth potential, and reduce barriers to entry for fund managers looking to operate in the VC market. The programme has backed 54 funds to date, representing c.£2.7bn of finance.
As the largest investor in UK venture and venture growth capital funds, the British Business Bank often makes cornerstone commitments, enabling funds to achieve a first close and helping funds to execute their planned strategy more effectively and often to a greater scale.
Adopting the strategy of its predecessors, Longwall 4 will continue to target UK based start-up and early-stage science and engineering deeptech companies across a range of sectors, including the Industrial Strategy sectors of Advanced Manufacturing, Clean Energy, Defence and Life Sciences.
Fund 4 is targeting investing between £500k and £2m into 14-16 companies with a significant amount of capital reserved for follow on investments. It has already raised £86.2m and is targeting £100m at close.
Mark Sims, managing director, head of development equity funds, British Business Bank said, “The Enterprise Capital Funds programme plays a crucial role in helping early-stage funds raise capital with a cornerstone investment, increasing the amount of scale-up finance available for high growth early-stage companies. With businesses like OrganOx already pushing the boundaries of what’s possible, our continued partnership with Longwall Ventures will help uncover the next generation of breakthrough technologies and UK success stories.”
Business secretary Peter Kyle said, “British Business Bank’s investment into Longwall Venture’s new fund will provide a major boost to start-ups across key growth sectors and is a shot in the arm for the UK’s thriving technology sector.
“This news demonstrates how this government is using our Modern Industrial Strategy to deliver long-term growth and opportunities that support skilled jobs and raises living standards across the UK.”
Elizabeth Bailey, director, Development Equity Funds, British Business Bank said, “The Bank has a longstanding relationship with Longwall Ventures, having made four investments since its inaugural fund in 2008. Longwall’s strategy of backing our most promising companies in key sectors helps create more jobs and drives wider economic growth. The Enterprise Capital Funds programme has backed 54 funds to date, highlighting the value of the programme and the positive role it plays in the venture market.”
David Denny, managing partner, Longwall Venture Partners LLP said, “The UK’s strong research base across academia and industry has created a rich seam of opportunities to turn groundbreaking science into valuable businesses but these businesses often struggle to raise long-term capital to support them on their journey to commercialisation. We are excited to find the next crop of deeptech investments for our new fund.”