media sociologist, free-lance author and activist, has studied and conducted research on the knowledge order of digital media, on copyright and the knowledge commons at Free University Berlin, Tokyo University, Humboldt University Berlin and University of São Paulo. Since March 2021 he is Senior Researcher in the H2020 project European Media Platforms (EuMePlat) at the Hans Bredow Institute Hamburg. Most recently he taught at the Institute for Media Studies at Ruhr University Bochum (May 2020-February 2021). Before, he was Fellow at the Center for Advanced Internet Studies (CAIS), Bochum (April-September 2019) and headed the research project „Public Service Media 2.0“ (2012-2015) at the Centre for Digital Cultures (CDC) at the Leuphana University of Lüneburg, which investigated the future of public service media. He was project lead of the conference series Wizards-of-OS.org and of the copyright information portal iRights.info, co-founded mikro-berlin.org, privatkopie.net and CompartilhamentoLegal.org, is board member of Digitale Gesellschaft e.V., member of C-Base.org and C3S.cc and blogs at vgrass.de.