About Me

I am a partner in our international Intellectual Property Group in London, offering specialist expertise in pharma and biotech litigation advice, in the UK and across Europe.

My work also involves the preparation of validity, infringement and 'freedom to operate' opinions in a variety of technical fields, as well as advising companies on strategies for protecting their IP rights. I work regularly with my colleagues across the Bird & Bird network to co-ordinate international patent litigation strategies.

In the pharma sector, our clients' commercial plans typically involve a product launch in several countries in Europe (and elsewhere). Therefore the legal/patent strategy invariably takes a similar multi-national approach. A major part of my day-to-day work for clients is co-ordinating patent disputes in several countries - usually the 'Big 5' pharma markets - UK, Germany, France, Italy and Spain. I assist clients in maintaining a consistent legal position between parallel disputes in the US courts, in the European Patent Office and in national patent courts around Europe. US clients in particular like to be able to rely on a single point of contact in this co-ordination work, and I can use my common-law background and knowledge of the various EU jurisdictions to effectively guide them through the litigation process in Europe.

Another key focus is Israel, a key hub for the biotech and hi-tech industries. I am a member of the firm's Israel Steering Group and visit Israel regularly, speaking at conferences and meeting with SMEs and start-ups. A particular interest of mine is guiding small companies through European patent litigation in as cost-effective a manner as possible. Small clients are often fearful of patent litigation in Europe but there are ways and means of steering the client through the dispute without breaking the bank.

As well as speaking and writing on IP issues, I am an associate member of the Chartered Institute of Patent Attorneys and Bird & Bird's representative at the Intellectual Property Lawyers Association.


  • Trinity College Dublin, BA, Natural Sciences (Microbiology)
  • College of Law, London, CPE & LPC
  • Queen Mary University of London, Masters in Intellectual Property


  • Law Society of England & Wales in 1998
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'A silky-smooth coordinator of pharmaceutical and biotech suits across Europe and the world'

IAM Patent 1000 2020

'Kelleher's pharmaceutical legal opinions are well regarded by all connected to the field'

IAM Patent 1000 2019

The 'seriously experienced' Kelleher has faced off against some of the most feared litigators around and emerged victorious.

IAM Patent 1000 2018

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