The creation of the Unified Patent Court (UPC) is the most prominent change in the European legal landscape for the last four decades. This book explains how the new system works in practice and how to make the best use of its provisions. It offers readers an in-depth and comprehensive commentary on the legal mechanisms of the upcoming ratified European Patent Law, and advice on potential problems that users of the forthcoming regulations may face. The book first describes the creation of the Unified European Patent Law and how its four new legislative texts interact. The new legislative texts are then explained and commented on in detail, rule by rule, with diverse approaches and perspectives from a practitioner team comprising patent litigators, European patent attorneys, law professors and patent judges. The Commentary takes into account the practical needs of users of the new system on both the prosecution and enforcement sides, addressing substantive and procedural problems. This book is the most authoritative text on the Unitary Patent and Unified Patents Court, and an invaluable tool for practitioners in this rapidly developing area of law.