WHEN MY DAUGHTER WAS SMALL, and possessions, to her, held talismanic qualities, I would frequently extoll the virtues of sharing. Sharing was something that didn’t seem to come naturally to her but had to be learned. In an attempt to sell my daughter on the idea of sharing, I emphasized the benefits in terms of both social capital (“People won’t like you if you don’t share”) and access to a wider range of goods, promising a kinder-commons (“If you share with others, they will share with you”). As will become clear, I am not so unequivocal about sharing in the realm of digital data, though many are. Mirroring my parental evangelism regarding sharing, there is a dominant discourse that emphasizes the advantages of digital sharing. This short book builds on almost a decade of research I have conducted into the politics of transparency and secrecy to consider a form of subjectivity and a politics produced by the calls that are made on citizens and states to share and be transparent and render data open. I will argue that it is not simply an irony that such calls are made alongside a continued investment in infrastructures and practices of state secrecy and forms of closed data. Rather, both open and closed data practices produce what I call a shareveillant subject.