Martyn Tennant Partner and Head of Corporate and Commercial
Corporate and Commercial
Martyn Tennant is a highly regarded corporate lawyer and the trusted advisor of choice for ambitious businesses navigating complex transactions. With a primary focus on mergers and acquisitions, private equity, and corporate restructuring, Martyn advises businesses of all sizes—from high-growth start-ups to listed companies—on both a national and international scale.
After earning his Law LLB (Hons) from Durham University, Martyn qualified as a solicitor in 2007. His rapid rise in the legal profession saw him promoted to Partner at Swinburne Maddison in 2010—just three years after qualification—before taking the helm as Head of the Corporate and Commercial team in 2011. Under his leadership, the department has expanded significantly, playing a central role in some of the most high-profile transactions in the North East.
Martyn’s unique perspective stems from his own experience in business growth, having been instrumental in Swinburne Maddison’s transformation from a firm of 30 employees to one of the region’s leading law firms. This deep commercial insight enables him to provide strategic, pragmatic advice tailored to the realities of running and scaling a business. Since 2019, he has also been a member of the firm’s Management Team, playing a pivotal role in Swinburne Maddison’s strategic growth.
Passionate about fostering business growth in the North East, Martyn takes pride in working on transformative deals that contribute to the regional economy and create lasting value for local businesses. He works closely with business owners, private equity investors, and corporate stakeholders, providing insightful, commercially focused advice on growth and exit strategies. His clients value his ability to simplify complex transactions, anticipate challenges, and deliver solutions that align with their long-term business objectives.
- Mergers and Acquisitions
- Private Equity and Venture Capital
- Joint Ventures
- Corporate Reorganisations and Strategy
- Partnerships
With over 15 years of experience, Martyn is a leading figure in corporate law, particularly in transactional services. His expertise spans mergers and acquisitions, private equity and venture capital, joint ventures, corporate reorganisations, and strategic partnerships across various sectors including; hospitality, energy, manufacturing and engineering, professional services, healthcare and transport.
As Head of the Corporate and Commercial team, Martyn oversees the firm’s transactional practice, leading teams on regionally significant high-value deals, often with values in excess of £30m. He specialises in advising owner-managed businesses on the legal aspects of their growth and exit strategies, ensuring deals are structured efficiently and effectively for all parties involved.
Recent career highlights include:
- Led the sale of Amberstone Security Group Limited to US-based Argenbright Security LLC.
- Retained as a trusted advisor for Argenbright Security LLC in the acquisition of The Protector Group.
- Advised on the sale of NB Medical Limited to private equity-backed Agora Education.
- Guided the acquisition of Genesis Brands Limited by French multinational Geflor.
- Advised on the sale of John Wade (Transport) Limited and Stonegrave Aggregates Limited to Ashcourt Group Limited.
Martyn’s extensive commercial experience—both as a legal advisor and a firm leader—gives him a unique understanding of the challenges businesses face. His pragmatic, solution-focused approach sets him apart, making him a trusted partner for clients seeking strategic corporate advice.
Described as a ‘Transactional expert and exceptional corporate solicitor’, Martyn was named as a Leading Partner in the 2026 edition of the Legal 500, highlighting his corporate and commercial expertise. Prior to this, he was consistently recognised as a Leading Partner in the previous seven editions.
Prior to his recent successes in The Legal 500, Martyn was widely recognised for his expertise early in his career. In 2015, he was named Young Lawyer of the Year at the Northern Law Awards and Corporate Lawyer of the Year at the North East Dealmaker Awards.
"Martyn Tennant is an exceptional corporate solicitor. He understands business as well as the law and combines the two brilliantly into clear, concise advice and detailed insight into the deal."
"We would have no hesitation in recommending Martyn Tennant to any potential clients who require advice on a wide variety of issues."
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