The master itf file is the unique file that will be used to generate licenses for your customers (see Documentation chapter “Generating master itf files”).
This type of file is different from a regular itf file and only works with the marketplace. So you can’t use it for any purpose other than to sell your products on the site.
In order to be able to export MasterITF files, it is mandatory to be an approved seller be identified as such in your ProRealTime platform. For this you have to generate a vendor IDs and set it up into your platform (see Documentation chapter “Link your platform to a marketplace seller account).