@davidfor: at least if you do not send the pdf via amazon email they don't. Probably most people convert pdf anyway and researchers jprobably still just print their articles
. I think they use different formats on different kindles and as kovidgoyal said they would have to be reverse engineered.
I found some code that tries the reverse engineering but it dates from 2011 and is for .pdr which is not the format used on my paperwhite.
https://code.google.com/archive/p/ki...kis/Usage.wiki