Cameron Marshall


Cameron focuses exclusively on the biotechnology and pharmaceutical fields, with an extensive EPO opposition practice (including many cases defending against multiple opponents) that runs alongside a large prosecution practice. These two areas often overlap, so strategic prosecution and parent/divisional strategies are a regular part of his workload. He is often engaged to advise clients at an early stage, in situations where future patent fights with competitors are inevitable.

Cameron acts for biotech companies including Guardant Health and Mammoth Biosciences, but most of his time is spent acting for blue-chip pharmaceutical companies, including Novartis, Merck, Gilead, and Lilly. This work includes defending patents covering blockbuster products which have attracted numerous EPO oppositions, whether from traditional generics companies or from biosimilars. He often acts as lead counsel at the EPO, but also collaborates with other firms to provide a second pair of eyes, and frequently plays a support role for national litigations.

Cameron has over 25 years of experience of inter partes proceedings at the EPO, both defending and attacking, and he is one of only a handful of attorneys to have represented a patentee in an EPO opposition (and subsequent appeal) involving more than 15 opponents. This experience means that he is often engaged to defend patents which provide crucial protection and exclusivity for blockbuster pharmaceuticals and biologics, including patents on new medical uses, dosing regimens, and formulations. In addition to that work, though, he also handles biotech innovations and has recently been defending Guardant’s groundbreaking work on liquid biopsy against several opponents. His biotech work goes back a long way, and he defended the “Southern” patents on DNA microarrays and spent two decades working on the inventions underpinning lifesaving meningococcal vaccines.

The main independent guides to the legal profession regularly rank Cameron at the top of his field. He is recognised as a “highly experienced litigator” (JUVE 2023) with “great business acumen and a strategic mind” (Chambers & Partners).

As well as advising on patent matters, he was a tutor for several years on the JDD residential course preparing candidates for the EQE opposition paper, and was an advisor to the IP monitoring group of the UK Government’s Human Genetics Commission.

Cameron graduated from the University of Oxford where his work on the folding thermodynamics of fibronectin type III modules was awarded the university research prize and contributed to his first class degree.

Cameron Marshall is “a personable chap who is phenomenally bright and has a technical mindset, which makes him a formidable opponent.”
Chambers & Partners


  • BA (Hons) Biochemistry (University of Oxford)
  • MBiochem (University of Oxford)
  • Chartered Patent Attorney
  • European Patent Attorney
  • UPC Representative

Key Cases

  • AFINITOR® – acting for Novartis in defence of various medical use patents against numerous opponents.
  • BEXSERO® – acting for GSK in defence of patents covering key meningococcal vaccine antigens.
  • COSENTYX® – acting for Novartis in defence of patents relating to its best-selling antibody.
  • DOVOBET® – acting for LEO Pharma in defence of several topical combination and formulation patents against various Gx.
  • FORSTEO® – acting for Lilly against biosimilars in defence of peptide formulation and medical use patents.
  • ISENTRESS® – acting for Merck to revoke Shionogi patent on HIV integrase inhibitors.
  • KEYTRUDA® – defending Merck patents protecting formulations and medical uses of this best-selling antibody.
  • LUCENTIS® – acting for Novartis against various biosimilar companies in defence of several patents covering delivery of this Fab fragment to the eye.
  • XOLAIR® – acting for Novartis in defence of patents relating to formulating this blockbuster antibody.
  • Anti-CD47 antibodies – acting for licensee to defend Stanford patent against 7 opponents.
  • Anti-CGRP antibodies for migraine – defence of key patent against competitors.
  • Defence work for Guardant Health for its digital sequencing platform.
  • Sangamo – defence of zinc finger nuclease patents.
  • Oxford Gene Technology – defence of the ‘Southern’ patents on DNA microarrays against Affymetrix and others.