James Cox
Founding Partner
James founded Stonebridge as his family office to institutionalise his business activities. Over this period, he has built and exited multiple category-leading ventures—including Simba Sleep, which he scaled to $150 million in profitable global revenues and established as a market leader before exiting—and has led more than 15 high-impact growth investments across Stonebridge’s core themes. With a series of successful exits and a combined £5 billion in shareholder value generated (across current and exited investments), James’s leadership continues to guide Stonebridge’s mission to create enduring value for its stakeholders and portfolio companies
Ryan Thorne
General Counsel
Ryan is a qualified lawyer with deep expertise in M&A, private equity, and corporate law. He has held senior positions at BlackRock, Macquarie, and Freshfields Bruckhaus Deringer, providing him with a global perspective on strategic transactions. His legal acumen ensures that Stonebridge’s investments are positioned for resilient and responsible growth.
Michael Jackson
Venture Partner
Michael is a seasoned venture capitalist and entrepreneur with a distinguished track record in scaling and guiding high-growth ventures. He founded Elderstreet Investments VCT, achieving a successful exit to Molten Ventures, and has chaired multi-billion-pound FTSE 100 IPOs for companies such as Sage Group PLC and PartyGaming PLC. With deep expertise in capital markets and operational strategy, Michael’s leadership has consistently driven transformative growth. His commitment to innovation and strong governance continues to shape Stonebridge’s success and underscores our dedication to creating enduring value across our investments.
Jonathan Warburton
Venture Partner
Jonathan is Chairman of Warburtons, one of the UK’s most iconic bakery brands. Under his leadership, the company has reached market dominance and expanded globally, surpassing £500 million in annual revenues. His expertise in consumer goods and strategic growth adds invaluable perspective to Stonebridge’s mission of creating sustainable, long-term value.
David Newns
Venture Partner
David is a serial entrepreneur renowned for building and scaling ventures in the health and technology sectors. Having achieved two successful exits to FTSE 100 companies, he brings a unique understanding of both startup and corporate dynamics. His breadth of experience strengthens Stonebridge’s capacity to identify and nurture high-potential opportunities.
Richard Chapple
Venture Partner
Richard is a growth specialist and founder of The Growth Foundation, with a track record of driving market-leading expansions. Formerly serving as CMO at Gymshark and CEO at THG Ingenuity, he steered both brands to valuations exceeding £1 billion. His deep insight into brand-building and commercialisation aligns with Stonebridge’s focus on transformative opportunities.
Micheal Mylonas
Venture Partner
Michael is a seasoned investment banker, currently Managing Director and Head of Consumer Investment Banking at BTIG. Previously Head of Consumer at Jefferies and having held senior roles at The Coca-Cola Company, he has extensive experience in capital markets and consumer trends. His strategic guidance significantly enhances Stonebridge’s global reach and investment insight.
Paul Donoghue
Venture Partner
Paul is the CEO of Orlebar Brown, where he spearheaded the brand’s global growth and its acquisition by luxury group Chanel. With prior leadership roles at Radley+Co and Reebok, he has a strong track record in cultivating premium consumer brands. His passion for supporting emerging businesses complements Stonebridge’s commitment to delivering enduring value.
Richard Paul
Venture Partner
Richard is the co-founder of Nyman Lisbon Paul (NLP), specialising in financial strategy, business advisory, and M&A for high-growth companies. His extensive experience in structuring deals and guiding entrepreneurs through complex transactions has supported numerous successful scale-ups. This expertise further reinforces Stonebridge’s ability to drive sustainable, long-term growth.