Leythem Wall


Leythem is a European and UK Patent Attorney specialising in the chemical, consumer products, energy, material and medical sectors. Having worked in private practice and industry for European and US companies, in the UK and abroad, he is in a unique position to understand his clients' needs and provide a commercially focused service that adds value to their businesses.

Leythem’s specialties include European, PCT and UK patent drafting, prosecution, third-party observations, oppositions and appeals, opinions on infringement and validity, freedom-to-operate analyses and due diligence. Prior to HGF, he was a Partner in the London office of a major US IP law firm, and before then in house IP counsel for some of the world’s largest multinationals. He therefore has a wealth of experience in devising global patenting strategies, including drafting and prosecuting patent applications for succeeding in both Europe and the US.

He has particular expertise and substantial experience in Oppositions and Appeals, regularly representing clients in Oral Proceedings before the European Patent Office (EPO) as lead counsel in a wide variety of technical areas. He has won numerous defensive and offensive oppositions, including multi-party proceedings, and successful coordination with disputes in multiple jurisdictions such as UK, Germany, US, China, Japan, Korea, and India. Leythem also has a deep understanding of US post grant challenges (IPRs and PGRs), and how these can be most successfully coordinated with EPO oppositions.

Leythem is an active member of high profile IP organisations in the UK, Europe and US including the CIPA Litigation Committee, the IPO European Practice Committee, the RSC Law Group, and the European Qualifying Examination Committee (opposition paper). He is also on the Board of the European Patent Litigators Association (EPLIT), which promotes European patent attorney representation in the future Unified Patent Court (UPC). A frequent author and lecturer on patent law, Leythem has had numerous articles published in legal journals and spoken at a number of international programs and conferences in Europe, the United States, and Asia, as well as before numerous Fortune 500 companies.

A Chartered Scientist (CSci), Chartered Chemist (CChem), and a European Chemist (EurChem), Leythem has a Masters degree (first class) in Chemistry from Oxford University. He also has postgraduate certificates in IP Law (Queen Mary, University of London), IP Litigation and Advocacy (Nottingham Law School), and a diploma in Patent Litigation in Europe (University of Strasbourg).