Principles of Patent Law provides comprehensive coverage of the policies, laws, rules, and practices of the U.S. patent system in a format accessible to students, lawyers, government officials, and business people. The Seventh Edition builds on the strengths of prior editions in combining discussions of the law and theory of patents with instructive case materials. The Seventh Edition features a number of significant changes designed to reflect the "new normal" with respect to various aspects of U.S. patent law, including (1) the revitalization of jurisprudence on subject-matter eligibility, (2) the ongoing transition to dominance of patentability provisions adopted by the America Invents Act of 2011 (AIA), and (3) the increased roles of administrative proceedings and administrative-law concerns in patent law practice. In response to such developments, we have reorganized the chapters on patentability essentially to follow the order of 101 to 103 and 112 in the Patent Act. In the chapters on novelty and nonobviousness, we have generally placed the primary focus on the AIA formulations of these requirements, with pre-AIA law now tending to appear in a more secondary role. We have also introduced a new, separate chapter on "Procedures and Institutions" of patent law. We hope that the result is a spryer casebook that stays true to the vision of the First Edition.