How is music appropriated and recirculated on the web, across different claims to authority over its movement? Complicating broad accounts of online ‘piracy’ or ‘sharing’, this paper explores rules of appropriation and recirculation in the field of archival hardcore blogging, in close readings of blogs that try to reconstruct a system of regulating principles and regulated practices. In relations among themselves, bloggers claim (and quarrel over) a non-proprietary ‘custodial’ authority over the music they post, which supports a range of privileges from attribution to exclusivity. Relations between bloggers and property-holders reveal intricate entanglements of different forms of authority (rather than straightforward oppositions between discrete logics of gift and commodity) – in which bands and labels might appeal to subcultural credibility in the same breath as legal copyright. While drawing on concepts of norm and gift that emphasise and valorise the sociality of appropriation, this paper insists on the ambivalence and contestation across different practices of appropriation, and between practices of appropriation and property – recovering an intricate interrelation among the legal, economic and social lives of musical works.