This new book provides a comprehensive overview of the topic of patent claim interpretation in the UK and in three other select jurisdictions. It explores territory that has great commercial significance and yet is severely under-explored in existing works. The twin issues of the function of patent law and interpretational analysis of the scope of protection have been recently reconsidered by the House of Lords, and this work not only reviews their recent cases but also looks at how the US, German and Japanese patent systems deal with the complex problems presented in this area. The book provides a balanced approach between practical, academic and theoretical approaches to claim interpretation. In doing so, it provides more than a simple case analysis, as it enables the reader to consider the shape that the law should take rather than simply recounting the current position. Its novelty therefore lies in bringing the theoretical elements of the discussion together with the view of the profession charged with creating the patent documentation in the first place and then viewing this in the light of the detailed comparative studies. It is only by considering all of these elements that we begin to see a pathway for the development of the law in this area. This is a work that will be an important source of reference for academics and practitioners working in the field of patent law.