Books and other media typically have an additional "supplemental" bar code next to the EAN-13 bar code. This bar code is only useful to the publisher, and cannot be used for any listing and searching purposes. Here is an example of an EAN-13 bar code with a smaller 5-digit supplemental bar code (52995) printed to the right of it:

Many laser scanners (in particular the Microvision Flic) will include this bar code with an EAN-13 scan if the laser beam is allowed to cross over into it, which might prevent a program from recognizing a scan. The following "Disable Supplemental" command will prevent supplemental bar codes from being included with an EAN-13 scan:

Print this page from your browser, then scan the "Disable Supplemental Codes" bar code into your scanner. This command will prevent the "supplemental" bar code from being scanned in. It is especially useful when using the standard Microvision Flicware or Scanner Wedge drivers.

FlicwarePro/AutoISBN and ScoutPalSE and users do not need to disable supplementals, but it's ok if they do. It may speed their scan transmission rate up slightly, and it will free up more memory when using their scanner in batch (untethered) mode.