Mark Chacksfield QC

CALL: 1999 | SILK: 2019
Formerly a sector leading IP junior, having taken silk in 2019 Mark is now forging an impressive reputation as an innovative and responsive silk in complex pharmaceutical, biopharmaceutical and telecoms patent actions.

Mark has appeared in many of the leading patent cases over recent years, where he has a stellar reputation, but also attracts a loyal following across the entire range of IP and media cases.

He is praised for his deep understanding of the law, innovative and inventive mind, and his impressive work ethic.

  • Experience

    Patents & SPCs

    • Actavis Group PTC EHF v ICOS Corp[2017] EWCA Civ 1671: the leading Court of Appeal decision considering the correct approach to obviousness attacks based on the performance of routine but potentially unpredictable research, now on appeal to the Supreme Court.
    • Fujifilm Kyowa Kirin Biologics Co Ltd v AbbVie Biotechnology [2017] EWHC 395 (Pat): the first ‘Arrow declaration’ case to have come to trial, paving the way for the subsequent explosion in interest in this novel form of relief; Mark having also appeared for Arrow in the original case.
    • Unwired Planet International Ltd v Huawei Technologies Co Ltd[2017] EWCA Civ 266:  the first of the Unwired Planet cases to come to appeal, and was the subject of intense attention from the industry. Having succeeded at first instance, Unwired Planet successfully defended the entire judgment on appeal, paving the way for the much discussed FRAND action.
    • Hospira UK Ltd v Genentech Inc[2016] EWCA Civ 780: This was the second appeal in the trastuzumab litigation, relating to Genentech’s blockbuster antibody Herceptin, and which raised acutely the question of obviousness in an empirical field having regards in particular to the earlier Court of Appeal decision in Teva v Leo.
    • Teva v Leo [2015] EWCA Civ 779:  This appeal has been described as one of the most important judgements of the Court of Appeal for the pharmaceutical industry in recent times, and concerned the question of obviousness in empirical fields: is it enough that it is obvious to test a particular compound to find out if it works, or does it have to be obvious in advance what the results of that testing will be?

    Jurisdiction & Remedies

    • Chugai Pharmaceutical Co Ltd v UCB Pharma SA[2017] EWHC 1216 (Pat): this was an application to strike out a claim for want of subject matter jurisdiction which concerned the limits of the power of the Court to consider matters said to engage the validity of foreign patent rights.
    • Fujifilm Kyowa Kirin Biologics Co Ltd v Abbvie Biotechnology [2017] EWCA Civ 1: This was an appeal from the first instance decisions of Henry Carr J (on subject matter jurisdiction) and Arnold J (on personal jurisdiction) in litigation concerning the availability and scope of ‘Arrow declarations’ relating to the world’s largest pharmaceutical product, Humira.
  • Education & awards
    • BA in Natural Sciences (Zoology) 1st class, Clare College, Cambridge 1997
  • Professional memberships
    • Chancery Bar Association
    • Intellectual Property Bar Association
  • Hobbies & interests

    In an earlier life Mark was a keen sportsman, fencing at a national level, coming 2nd as an U20 epeeist, and once squeaking into the top 8 in the national championships. He was also a committed modern pentathlete, obtaining his Blue at Cambridge. Now, however, his exercise is mostly limited to carrying boxes of papers, an occasional run home from chambers and kicking a ball around with his three much loved children. He also remains involved in modern pentathlon, through a charity set up by Mark and two of his team mates (now with 200 supporters) to raise funds for, and generally assist with, the Cambridge University club. Mark also loves to travel, good food and music (mostly of the type with irritating repetitive beeps).

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