The invention relates to a method for checking the presence and/or readability of an item of product information, in particular an item of packaging content information. An item of product information, in particular packaging content information, is applied to the product, in particular packaging, by using a printing device. A means of identification is applied by using the same printing device; and the product, in particular the packaging, is scanned with a reader in order to ascertain whether the means of identification is present and can be read, the means of identification comprising a barcode and/or a smart code, individual lines of the barcode being aligned parallel to a direction of print application, and the reader comprising an optical reader, in particular a barcode and/or smart-code reader, preferably a barcode and/or smart-code scanner.