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Catherine Mallalieu

Partner, Patent Attorney / London

Catherine Mallalieu

Practice area

Patents - biotechnology, chemistry & pharmaceuticals group
Patent litigation, arbitration & mediation group


Catherine is a highly experienced patent attorney who represents major international organisations across the chemical and biological sectors. In particular, she specialises in biotherapeutics, specialty chemicals, nutritional products, veterinary products and agrochemicals and in a number of diverse related technologies. Catherine has been successfully representing clients before the EPO since 1991 and has substantial experience in defending and opposing patents. In addition to multi-party oppositions, Catherine has taken a co-ordinating role in pan-European litigation.

As well as major international organisations, Catherine has advised numerous emerging companies and academic institutions on how to build value through their IP portfolio. This has often involved IP due diligence for mergers, project acquisitions and flotations.

Catherine gained valuable in-house patent experience having worked at Zeneca Agrochemicals, where she had particular responsibility for their bioscience and insecticide divisions. This combination of in-house experience as well as acting for major international organisations over the years has enabled Catherine to develop a highly commercial approach, which clients have appreciated.


"Clearly in the premier league of patent attorneys covering biotech in the UK" Managing IP.

"Excellent understanding of clients' commercial interests" Legal 500.

"On the life sciences side, Catherine Mallalieu is 'very reliable' and has an 'excellent legal and scientific background'" Legal 500.

Catherine became a partner at D Young & Co in 1997 and is a member of the Chartered Institute of Patent Attorney's Patents Committee. 


BSc in Chemistry, University of Birmingham.
European Patent Attorney 1991.
Chartered Patent Attorney 1991.
European Design Attorney.


Chartered Institute of Patent Attorneys (CIPA) and the CIPA Patents Committee.
European Patent Institute (epi).
American Intellectual Property Law Association (AIPLA).

Selected Publications

Contributor to Chartered Institute of Patent Attorney’s European Patents Handbook.

View Catherine's profile on LinkedIn


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