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Marc co-founded Keidan Harrison LLP in May 2020. He is recognised by the leading legal directories as one of the UK’s top disputes lawyers. Chambers & Partners describes him as “a great strategist”, and the latest edition of The Legal 500 says he is ‘’an exceptionally dedicated, inventive lawyer’’, with previous editions describing him as “a no-nonsense lawyer who gets results for his clients’ and has a ‘willingness to get stuck into difficult fights”.

Marc is widely recognised as being among London’s leading disputes lawyers. He advises on high value commercial and financial litigation and international arbitration across a range of industry sectors (including financial and professional, IT/tech, commercial property, manufacturing, mining and commodities). His expertise includes commercial agency and joint venture disputes, civil fraud and asset tracing cases, as well as partnership/LLP, shareholder and corporate disputes. He is experienced in bringing and defending claims for interim relief, including worldwide asset freezing injunctions.

Marc undertakes professional negligence actions, acting predominantly against investment managers, construction professionals, and law and accountancy firms. He also advises on substantial corporate insolvency (in relation to winding up petitions, cases involving officers of the company and third parties, including alleged claims of misfeasance or fraud) and personal contentious insolvency matters. Much of Marc’s work has an international dimension and he has undertaken extensive work with EU, US, CIS, India and Africa dimensions, as well as cases connected to offshore centres.

Marc is well known for his work in the field of banking and financial disputes, where he advises professional counterparties, such as hedge funds and commercial bank customers, in high-stake and cutting-edge litigation against financial institutions, sometimes involving allegations of fraud. He is experienced in acting in high value disputes in the funds sector, including acting in LLP disputes where he assists departing members with negotiation of their exit, avoiding the need for litigation. Marc’s international arbitration work includes substantial cases across a range of industry sectors, including energy, mining and other commodities, as well as bringing and defending challenges to arbitration awards in the English Court (under ss68 and 69 of the Arbitration Act 1996).

Marc has very significant experience of managing complex High Court trials and other substantial hearings, as well as expertise in assisting clients to resolve disputes through mediation and other forms of alternative dispute resolution (ADR).

What the legal directories say

Marc has for many years been recognised by the Chambers and Partners Guide, his testimonials including the following:

“He is excellent – pragmatic and a pleasure to work with” (2021)

“great at strategic thinking and getting commercial results for his clients” (2020)

“very energetic, engaged and hands-on, and really client-focused” (2019)

“solutions-focused” and “a great strategist” (2018)

“a hugely energetic lawyer, a creative thinker and leaves no stone unturned” and “absolutely passionate and determined” (2017)

“simply on the ball the whole time” (2016)

Marc has also in recent years been mentioned by The Legal 500 Guide in the Commercial Litigation, Civil Fraud, International Arbitration, Partnership, Professional Negligence and Banking Litigation categories. For both Banking Litigation and Commercial Litigation, he is ranked in the Legal 500 2022 Guide as one of a small number of ‘Leading Individuals’ in these fields based in London. Recent and past testimonials have included:

“an exceptionally dedicated, inventive lawyer real team player”

“a real team player”

“bright and wholly committed to getting the right result for the client”

“goes the extra mile”

“particularly proactive approach”

“great instinct for what approach is most likely to succeed”

“a force of nature, who is irrepressibly energetic, absolutely determined to find the right strategic solution, and hugely client-focussed”

“ever-sensitive to the client’s commercial – and cost – needs”.

Marc was listed in Thomson Reuters’ London ‘Super Lawyers’ for Commercial Litigation.

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