Originally Posted by HarryT
I'm not sure that's true, DD. I think Amazon recognise the book from its ASIN identifier, which is not changed by removing the DRM. Eg, you'll still see the popular highlights in a book (if you have that enabled) even with DRM stripped.
You're right, of course. But the popular highlights and synchronization was not the "in that regard" I was referring to.
I was referring to the book's downloaded status: as in the DRM-free version being on the device is never going to cause the original version to NOT appear in the archive (and vice-versa: deleting the DRM-free version from the device won't make it appear in the archive). Unless you would happen to delete the original purchase from your Amazon library entirely, and then send the DRM-free version to your device as Personal Document and you have personal document synchronization set up. I
wouldn't recommend sending DRM-free versions of Amazon purchases back through Amazon's own system, but that's just me.