Despite the substantial benefits of standards in today舗s economy, the recent advent of standard essential patents (SEPs) 舒 which protect proprietary technologies essential for industry standards 舒 has tended to create a setting for anticompetitive practices that, at least potentially, harms competition and consumer welfare. An opportunistic SEP owner can intentionally conceal the existence of its patents during the standardization process, or later hold up manufacturers and impose on them exploitative licensing conditions. This book, through an intensive focus on case law in the United States and the European Union, clarifies the scope of competition law in addressing SEP owners舗 opportunistic conduct, and offers the first comprehensive analysis of the antitrust liability an SEP owner might face in each jurisdiction.