“Matching the rigour of the analysis with an extraordinary pedagogical capacity, the authors unveil all the arcana of the ‘openness’ capitalism model and digital labour. Essential for scholars and students across the social and economic sciences.” (Carlo Vercellone, Université de Paris 8, France) “This vital book is an objective and detailed assessment of the private capture of common value, concluding with an in-depth survey of what commons-friendly public authorities could do to defend the new ‘common-wealth’.” (Michel Bauwens, Founder of the P2P Foundation, The Netherlands) “An outstanding analysis of how digital capital uses openness as principle of capital accumulation and exploitation. A must-read for everyone who wants to understand what the internet and digital media are all about.” (Christian Fuchs, University of Westminster, UK) This book tackles the concept of openness (as in open source software, open access andfree culture), from a critical political economy perspective to consider its encroachment by capitalist corporations, but also how it advances radical alternatives to cognitive capitalism. Drawing on four case studies, *Corporate Capitalism’s Use of Openness* will add to discussion on open source software *,* open access content platforms, **open access publishing, and open university courses.** ** These otherwise disparate cases share two fundamental features: informational capitalist corporations base their successful business models on unpaid productive activities, play, attention, knowledge and labour, and do so crucially by resorting to ideological uses of concepts such as “openness”, “communities” and “sharing”. The authors present potential solutions and alternative regulations to counter these exploitative and alienating business models, and to foster digital knowledge commons, ranging from co-ops and commons-based peer production to state agencies’ platforms. Their research and findings will appeal to students, academics and activists around the world in fields such as sociology, economy, media and communication, library and information science, political sciences and technology studies.