One of the most pressing antitrust issues today involves settlements by which brand-name drug companies pay generic firms to settle patent litigation and delay entering the market. Whether this activity constitutes an antitrust violation is a subject that has occupied courts and enforcement agencies around the world. This article focuses on the law in the United States, where the law is most developed. It explores the issues courts have addressed after the Supreme Court’s 2013 decision in FTC v. Actavis, including payment, the patent merits, the Rule of Reason, pleading requirements, causation, and state law. The article also analyzes European law and enforcement, in particular seven monitoring reports and two significant rulings against companies. Finally, it briefly discusses developments in the UK, Canada, India, and Korea.