Quote:
Originally Posted by jhowell
Books delivered by Amazon to a Kindle device or app contain a "watermark" metadata field that identifies the Amazon account for which the book was downloaded among other things.
In MOBI and KF8 (azw3) formats the watermark is stored in field number 208 of the EXTH header. KindleUnpack includes this as a comment in the OPF file it creates when converting to EPUB.
In KFX format that field is contained in a separate voucher file. That file contains all of the user-specific information about the book as well as the DRM encryption keys needed to decrypt it. The rest of the files that make up a KFX book are identical across users.
A .kfx-zip archive typically contains all of the files associated with a KFX format book, including the voucher with the watermark. A .kfx file from which DRM has been removed does not contain anything from the voucher and so does not have any personally identifiable information. |
Not even images? That's good to know, thank you.