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Stewarts Law LLP

Work 0113 222 0022
Fax 0113 222 0044
Leeds, London

Jonathan Sinclair

Work 0113 222 0022
Stewarts Law LLP

Work Department

Competition Litigation


Partner in the Competition Litigation department. Jonathan has for over 25 years acted as lead partner for global businesses spanning a wide range of sectors in complex damages claims and, in particular, cartel cases.


A proactive leader in the development of cartel damages cases, Jonathan has been an innovator in the field, advising many FTSE 100 and global companies on the strategy and conduct of such disputes.

Jonathan has extensive experience advising major companies on case strategy and the effective resolution of high-value claims. In recent years, this has included initiating the high-profile interchange fee litigation and claims in relation to the LCD, CRT and high voltage power cable cartels among many others.

Jonathan is consistently recognised as a pre-eminent specialist in competition and commercial litigation. He established and developed the firm’s Competition team (and previously the Commercial Litigation team in Leeds) from scratch. Both teams are now recognised in the top tier of the legal directories in these fields. He has been described as “a top litigator” and “incredibly bright and quietly persuasive”.


Jonathan has published or contributed to articles on various aspects of competition litigation claims including a comparison of cartel claims in the US and UK/EU and has been interviewed on the BBC in relation to competition infringements in the banking sector.


Jonathan started his career as a commercial litigator at Clifford Chance after being awarded a first class degree at Oxford. He subsequently joined Eversheds, where he was a partner for 18 years and Head of Commercial Litigation for the firm. Jonathan joined Stewarts in 2009 to specialise in competition litigation, setting up and leading the firm’s dedicated team.


Prince Henry’s High School, Evesham; Oxford University (1979-82 BA Hons ancient and modern history (1st)).


Fell running and other outdoor pursuits in an increasingly fruitless attempt to keep up with three active children.

Yorkshire and the Humber: Dispute resolution

Commercial litigation: Leeds and West Yorkshire; North Yorkshire

Within: Leading individuals

Jonathan Sinclair - Stewarts Law LLP

Within: Commercial litigation: Leeds and West Yorkshire; North Yorkshire

‘A first-class litigation boutique’, Stewarts Law LLP is ‘easily one of the best for litigation outside of the Magic Circle’ fielding ‘a strong team with a sense of purpose’ that is ‘undoubtedly the premier firm in Yorkshire, maybe even nationally’. The group is highly regarded for its experience in cartel damage claims, financial services disputes, fraud matters and investigations. Mo Bhaskaran, who ‘strikes the right balance between aggression and realism’, leads the department, which also fields the ‘tenaciousKate Pollock, who is ‘efficient and a popular team leader for competition work’; the ‘absolutely brilliantJonathan Sinclair and senior associate Nick Haworth, who is ‘a savvy litigator with a bright future ahead of him’. Highlights included Pollock representing multiple corporates in cartel actions relating to interchange fees charged by MasterCard on debit and credit card transactions, Sinclair acting in cartel actions against Visa relating to interchange fees and Ian Gatt QC representing Iiyama in damages proceedings relating to a cathode ray tube cartel. Marks and Spencer, Wm Morrison, Home Retail Group and B&Q are also clients. Martin Walsh made partner in 2018.

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