Abstract : In the past decade, parliaments in industrialized countries have been pressured to adopt more restrictive legislation to prevent unauthorized file sharing and enforce higher standards of digital copyright enforcement over entertainment media and computer software. A complex process of supranational and national lawmaking has resulted in several legislatures adopting such measures, with wide variations in content and implementation. These policy developments offer an interesting research puzzle, due to their high political salience and to the amount of controversy they have generated. Specifically, the introduction of harsher intellectual property regulations has resulted in intense online and offline collective action by skilled activists who have contributed to altering the digital copyright policy field over the years. In France, the DADVSI and HADOPI laws on digital copyright infringement have been actively contested by grassroots movements all along their chaotic route through Parliament. Similarly, at the European level, the Telecoms Package Reform has given rise to an intense protest effort, carried by an ad hoc coalition of European activists. In both cases, online mobilization was an essential element of political contention against these legislative initiatives. In both cases, our analysis shows how online mobilization and contention can substantially affect policy-making by disrupting the course of parliamentary lawmaking at both the national and European levels. We provide an analytical framework to study these processes, as well as a detailed analysis of the frames and digital network repertoires involved in the two cases under scrutiny, with reference to the nascent research agenda formed by the politics of intellectual property.