Performing an object such as ‘the economy’ hinges on practices of formatting knowledge. The article proposes to look at such instituting moments in connection with social conflicts over the legitimate rules of exchange. This is exemplified by way of recounting the story of the codification of Swiss bankruptcy law in 1889. In order to homogenize the legal procedures of debt collection and bankruptcy, two subject categories were instituted: ‘merchants’ and ‘non-merchants’. These different categories were thought to account for the diverging temporalities and spaces of credit exchange in everyday economic life. The intro - duction of the commercial register, a media-technical apparatus, enabled a formal distinction between ‘merchants’ and ‘non-merchants’. However, this boundary was contested and proved to be porose.