How US patent claims should be interpreted has been the subject of intense debate, and has been considered by the US Supreme Court three times since 1996. Following the recent decision of the Supreme Court in Festo Corporation v Shoketsu Kinzoku1 the rules have hopefully now become more settled. The decisions in the above three cases should be considered together, and the purpose of this article is to summarise the main points that can be gleaned from them and to consider their implications for European practitioners in their day-to-day work of drafting applications and providing instructions to their colleagues in the USA. Of course, where there is any difficulty, or where a legal opinion is required, there is no substitute for the advice of a US practitioner.
