Kieron O'Connell

Kieron O'Connell

Partner - Patent Attorney

Kieron is a UK and European patent attorney specialising in chemistry, with a particular focus on pharmaceuticals. Prior to joining Potter Clarkson, he gained experience as a postdoctoral researcher at the University of Cambridge and as a medicinal chemist in the pharmaceutical industry.

Kieron works with a range of clients, including universities and start-ups, SMEs, and multinational companies, and supports projects at all stages of drug discovery and development, from early lead finding and optimisation, through clinical trials and beyond. He also works with clients in the wider life science and chemistry fields.

He has extensive experience of patent drafting, international prosecution, and portfolio management, as well as advising on IP strategy, freedom-to-operate, and ownership/inventorship. He also has experience of attacking and defending patents through the European Patent Office’s opposition and appeal procedures and of supporting litigation in the UK High Court.

Kieron joined Potter Clarkson in 2014 from a position as a medicinal chemist at Takeda Pharmaceuticals in Cambridge, UK.



Chemistry and pharmaceuticals including organic chemistry, medicinal chemistry, new chemical entities, new and further medical uses of known therapeutics, formulations, drug development and process chemistry 


Kieron studied chemistry at the University of Reading before moving to the University of Cambridge to complete a PhD in organic chemistry. 


MChem (Hons), PhD (Cantab), UK and European Patent Attorney


Member of The Royal Society of Chemistry (MRSC)