Patent law is an important, fascinating, and rapidly changing field. This book was written for all who need to understand these recent changes, as well as for students in intellectual property courses. For those engaged in international practice, this work sheds helpful light on the key doctrines and theories underlying U.S. patent law.

More examples and explanatory material, as well as flow charts, have been included in this edition to provide some practical application of abstract or difficult concepts. The most significant areas of updated materials include the rapidly evolving law concerning statutory subject matter, nonobviousness, and the application of the America Invents Act. This work covers the latest U.S. Supreme Court decisions, including SAS Institute v. Iancu, Oil States Energy Services v. Greene's Energy Group, Helsinn Healthcare v. Teva Pharmaceuticals USA, and WesternGeco v. ION Geophysical Corporation.

The book also covers the major decisions of the U.S. Court of Appeals for the Federal Circuit. Each chapter has been comprehensively updated to reflect those decisions that refine, explain, or modify the existing state of patent law. The Federal Circuit's Thaler opinion regarding artificial intelligence exclusion from inventorship is explained, the World Trade Organization's consideration of the treatment of intellectual property for the COVID-19 vaccines is discussed, and material that explains the European Union's Unitary Patent System has been added to provide real-world examples of the concepts covered in the fourth edition.