Experience

Cases include:

• Acting for the claimant in one of the largest fraud cases in the UK courts, against 40 defendants, which went to trial for a full court year across 2025-26 (the longest ever commercial court trial). Our client’s claims were in excess of $1bn and the dispute was listed as one of the Lawyer’s top 20 cases of 2020 and again in 2025.
• Acting for a global IT infrastructure services provider in respect of major Technology and Construction Court litigation regarding a customer’s failure to migrate its IT infrastructure to a modernised system. Our client sought damages of £20m+ as the difference between the pricing under the contract and the actual costs of the services provided.
• A dispute between a UK government department and an international IT supplier following termination for breach of a £400m contract for transformation of the department’s IT estate. The dispute involved complicated expert analysis of multiple concurrent causes of delay.
• Advising the supplier on dispute resolution of a claim for tens of millions arising out of the termination of an IT modernisation project with a major international telecoms company.
• Successfully defending at trial, a claim by our client’s former business partner for c. £30m following the floatation of their company. Subsequently, acting for the same client in respect of a hard-fought trade dispute between rival suppliers involving injunctive relief and both civil and criminal allegations.
• Acting for a FTSE 100 company facing a £20m claim for software licence infringement by an aggressive US supplier.

Expertise

Martin has over 20 years of experience in litigating complex, high-value IT disputes. These are typically troubled development projects with delays in completion, functionality issues, performance issues, scope changes and cost overruns. He has acted for claimants and defendants in multimillion pound software licensing disputes.

He has extensive experience of major international fraud litigation, including jurisdiction challenges, service, freezing injunctions, asset tracing, foreign law evidence, international disclosure and quantum.

Martin acts for large corporate and public bodies in high-stakes disputes and is frequently reinstructed by repeat clients.

Recognition

Martin is recognised by Chambers as follows:

“Martin Walsh’s client service and commercial vision is very strong. He is very astute, responsive, and a pleasure to deal with”

“Martin Walsh is a star. He is very hardworking and a very good tactical lawyer, all around excellent.”

“Martin Walsh is a very impressive character who is very tenacious.”

Career

Martin has been a partner at Stewarts since 2018, having previously trained and qualified at Pinsent Masons.

Martin has written his career story and experience of Stewarts for our careers section, you can view his story here.

Personal

Martin enjoys most sports, particularly football and golf.