William has broad experience of biotechnological patent disputes from small molecules (e.g. Gilead v Idenix, Gilead v Nucana, Accord v RCT, Aspire v Alcon) to proteins/antibodies (e.g. Regeneron and Bayer v Amgen and others, Eli Lilly v Genentech, Takeda v Hoffman La Roche). William’s biochemistry background has provided a strong footing for this practice in biotechnological patents, where he has particular experience of litigating technically complex major patent disputes often with multi-jurisdictional issues.
He has also been involved in a significant number the major FRAND disputes which have occurred in the UK Courts including Philips v ASUS, Philips v TCL, Mitsubishi and Sisvel v Oneplus and others, Lenovo v Interdigital (both in the High Court and on appeal), Philips v OPPO and Panasonic v OPPO.
William has been ranked for 8 years by Chambers and Partners and is presently band 3 in Intellectual Property. William is also ranked band 3 in Intellectual Property by the Legal 500. Examples of quotes from Chambers and Partners about William from his rankings over the years include:
“He is a thoughtful and strong junior who thinks for himself and provides good support.” And that “He is the crème de la crème, and picks up technical issues with utmost ease.”
“Able and experienced junior who elicits praise from instructing solicitors for his work ethic, written submissions and advice.” and that “He has a phenomenal brain.”
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Experience
Patents & SPCs
- Bayer and Regeneron v Amgen and others (trial fixed June 2025) – a High Court case concerning Regeneron/Bayer’s VEGF-trap (Aflibercept) for the treatment of wet AMD.
- Panasonic v OPPO – another substantial FRAND dispute concerning terms for Panasonic’s SEP portfolio – settled very shortly before trial (Oct 2024).
- Philips v OPPO – Substantial FRAND dispute between Philips and Oppo concerning FRAND terms for Philips’ SEP portfolio settled very shortly before trial (Jan 2024).
- Samsung and Amgen v Alexion Pharmaceuticals (settled – 2023) a High Court case concerning Alexion’s patent concerning the treatment of aHUS.
- Gilead v Nucana [2023] EWHC 611 (Pat) – A High Court patent action concerning two of NuCana’s European patents allegedly covering Gilead’s sofosbuvir anti-viral medication. (William assisted until just before trial when he left for paternity leave).
- Interdigital v Lenovo [2023] EWHC 1583 (Pat) – A High Court FRAND dispute between Interdigital and Lenovo concerning Interdigital’s SEP portfolio in which William acted for Lenovo.
- Alcon Research v Pharmathen SA [2022] EWCA Civ 845 – an appeal concerning the respondent’s patent for fluprostenol isopropyl ester (travoprost) for the treatment of glaucoma.
- Novartis v Teva [2022] EWHC 959 (Ch) – William appeared for Zentiva SA successfully defending this interim injunction application arising from Novartis’ patent application.
- InterDigital v Lenovo [2022] EWHC 10 (Pat) – William appeared for Lenovo in this High Court technical trial before the FRAND trial in this telecoms/FRAND dispute.
- Eli Lilly v Genentech [2020] EWHC 261 (Pat) a High Court trial of a preliminary issue concerning res judicata of a divisional patent related to the Patent from [2017] EWHC 3114 (Pat) below.
- Mitsubishi Electric and Sisvel v Oneplus (and others) (settled shortly before trial) – William acted for one group of Defendants in this FRAND action concerning Sisvel’s SEP portfolio.
- Koninklijke Philips NV v Asustek Computer Inc [2020] EWHC 29 (Ch) a High Court case concerning FRAND licences, where Asustek sought to exit the case on similar terms to those in TQ Delta, settled shortly before trial.
- Takeda UK Ltd v F Hoffmann-La Roche AG [2019] EWHC 1911 (Pat) a High Court patent trial concerning glycosylated antibodies. The appeal has now been settled.
- Regeneron Pharmaceuticals Ltd v Kymab Limited [2018] EWCA Civ 1186 (and High Court first instance decision [2016] EWHC 87 (Pat)): A complex patent dispute concerning transgenic mice for the production of fully human antibodies. The Supreme Court hearing of this occurred in February 2020.
- Eli Lilly and Co v Genentech [2017] EWHC 3114 (Pat): Patent dispute about antibodies to IL-17 A/F, which came to trial in January 2019, with substantial jurisdictional interim disputes heard, currently under appeal pending January 2021, and a separate SPC claim about Article 3(a), and the “third party MA” issue.
- Sandoz v Searle [2018] EWCA Civ 49 (and first instance decision [2017] EWHC 987 (Pat)) : SPC dispute concerning the proper interpretation of Article 3(a) in the context of Markush claims, referred to the CJEU and co-pending with Royalty Pharma Sitagliptin – settled prior to EPO hearing.
- Accord v RCT [2017] EWHC 569 (Pat): High Court trial concerning the small molecule anti-epileptic drug lacosamide, with experts on scientific and US law issues – currently under appeal.
- Abraxis v Comptroller General [2017] EWHC 14 (Pat): SPC action brought against a refusal by the comptroller – reference made to the CJEU.
- GSK v Wyeth Holdings [2017] EWHC 91 (Pat): High Court patent action relating to meningococcal vaccines.
- Idenix Pharmaceuticals v Gilead Sciences [2016] EWCA Civ 1089 (and first instance decision [2014] EWHC 3916 (Pat)): Substantial and complex patent dispute concerning broad Markush formula claims encompassing the HIV drug sofosbuvir, also involving experts of US law on priority issues.
- Unwired Planet v Huawei Technologies (Case D – settled): Complex telecoms dispute concerning the use of Hadamard codes for mobile telephone – base station syncing. Settled shortly before trial.
- Telecoms dispute, settled before issue after substantial involvement, concerning down-conversion techniques in radio signal reception.
Entitlement
- NovNat Tech Limited v Immaterial Limited
- William acted on behalf of the patent holder and inventor to prepare pleadings to defend against an entitlement claim at the IPO.
- Education & awards
- Combined Undergraduate and Masters in Biochemistry (Molecular and Cellular Biochemistry) from Oxford University (2010), (First Class)
- Graduate Diploma in Law from City University London (2011), (Commendation)
- Bar Professional Training Course from the Inns of Court School of Law, City University London (2012), (Outstanding)
- Eric Newsholme Prize for Biochemistry
- Fowler Prize for excellence in college examinations
- “Best Dad” Mug on fathers’ day 6 years running
- Professional memberships
- Intellectual Property Bar Association (IPBA)
- Chancery Bar Association (ChBA)
- Gray’s Inn
- Hobbies & interests
Loves cooking and home brewing (beer), enthusiastic father of two.
Contact William Duncan's clerks
Whilst barristers have a designated practice management team, all the clerks have the capacity and knowledge to assist in cases involving all counsel.