[Elfwreck]

Originally Posted by Lord Mahoney

Digital watermarking is a slippery slope. They certainly have the ability to make it visible, for example, when you try to print the ebook, or once a book has been transferred to more than 10 devices, or under any other arbitrary circumstances.

There is no way to add watermark that "kicks in when you print" an epub or mobi, because there's no native print-ability; they have to be converted through something to print--and for a "watermark on print" to work, it'd have convince the printer software to add it. Most print setups go for simplicity; adding details from metadata is an advanced feature.

There's no way to identify "transferred to more than 10 devices," either. A digital file has no way of tracking how many types of hardware it's been copied to; that would take an extra program attached to it. (I'm not sure it's possible anyway. What, it would notice if the file were copied from a hard drive to a backup server? To a flash drive? Burned to CD, and then recopied to another hard drive?)

Does it notice if it's on a memory card that moves between a Sony and a PEZ? Does it notice if it's on a flash drive and read with EPubReader in Firefox, and then opened with Sigil?

Files don't collect info about the storage media that hold them.

There are plenty of ways that personally-identifying info can be hidden in an epub, and probably a mobi file; if the epub isn't DRM'd, a dedicated user can find all that info. Most people won't ever bother.

Knowing how the technology actually works would lay a lot of paranoia to rest. A digital watermark could indeed be hidden in the metadata, in a way that probably sticks around through standard format conversions--but there's no way to make that info stick through, for example, a conversion to HTML files which are then printed to PDF. The resulting PDF won't carry the metadata.

I don't upload my purchased stuff to torrent sites and still much prefer not having watermarks in it, and if there was software available to "cleanse" it, I wouldn't think twice about running the files through it.

If you open a watermarked epub with Sigil, you can go through the parts and remove identifying data... if you can figure out what it is. (You may not recognize your purchase ID number, for example.)

Same goes for allowing Windows Media Player to tag your own CD rips with license information it finds on the Internet--it's just not something you want to do.

Very different situation. That's using specific software to add information; that software also inflicts additional information into its database. However, the files themselves are untouched; it's only the program that collects the info.

Watermarking is just a more passive-aggressive version of DRM, and there's a large group of people who will always fight DRM no matter what.

There are people who cover their windows with mylar to prevent flying saucers from spying on them, too. Not all privacy measures are reasonable, or based on rational concerns.