This book provides cases and materials from the online economy in each of the major areas of antitrust. Broadly speaking, it contains cases addressing two types of issues: e-commerce (1-800 Contacts, Google Shopping, Ohio v. American Express, etc.) and intellectual property issues related to the online economy (FTC v. Qualcomm, Huawei v. ZTE, etc.). The book is ideal for a seminar, but it can also used as a supplement in a traditional antitrust course . To facilitate using the book, it includes short descriptions of the doctrinal background for the materials provided. The book includes more secondary materials (on algorithmic collusion, personalized pricing, etc.) than is typical of a casebook, because some of these issues have not yet given rise to cases suitable for inclusion. The book also includes more European materials than is usual for a U.S. antitrust book, given that the EU and its member states have been at the forefront of antitrust enforcement in these areas; it provides additional context for U.S. antitrust students or lawyers to appreciate the European materials. The second edition includes, in addition to other updates to the first edition, materials on the Google and Facebook complaints filed by US enforcers and on the EU's Digital Markets Act and Digital Services Act.