An accompanying document for a printing substrate, which is to be printed in a printing press, is configured as an electronic data set that is stored in a memory of an RFID tag. Data relating to a production-preparatory generation of an adhesive surface, on the printing substrate to be fed to the printing press, is written into the data set. Data relating to the manufacturer of the printing substrate of to its supplier, and data relating to the manufacture of the printing substrate are also written into the data set. In the case of a commercial unit having a printing substrate that has been only partially printed during a production run of the printing press, the data set can be supplemented with data which, at least, characterizes an event. The event could relate to a break in the printing substrate or to changes to the commercial unit which occurred during the production process that was implemented in the printing press using the printing substrate of the commercial unit.