For "soft DRM" I mean a sort of watermark (for example, a section stating "This book has been bought by Jane Doe from ACME Inc") which does not protect the book from being copied but states who is the buyer.

Yes, I know that deleting the watermark is a piece of cake: I am not concerned with this. I am just wondering if this makes sense or not, and I have mixed feelings, but I can't tell whether it is the fact that with a physical book this does not happen or not. What are pros and cons, in your opinion?

  • 2
    "makes sense" is pretty subjective.
    – DVK
    Jan 1, 2014 at 19:44
  • @DVK - I would assume that makes sense here is asking if there are legitimate reasons that a "soft DRM" as described is not a popular, or at least occasionally utilized way to release copyright protected e-books. I would say this falls on the Good Subjective side of the line... if just barely
    – Chad
    Jan 2, 2014 at 2:48
  • To be explicit: I just published a little ebook with a publisher which only uses soft DRM. I am quite happy with this, and even if I know it is already present in the "underground market" I don't care, since I think that people who don't want to pay one euro would not buy it anyway. But I would like to know which is the consensus on the explicit "modification" of the book with the purchasing data. Steganography is another matter: if I don't notice it, there's no problem for me
    – mau
    Jan 2, 2014 at 12:13
  • @Chad - I was going to agree with you till I re-read Julian's answer. That seems on the bad subjective side.
    – DVK
    Jan 2, 2014 at 16:55

3 Answers 3


I don't know if there are studies into soft DRM, but there are studies on difference in behaviour between people that are anonymous and people that are not. The non-anonymous generally being more "honest".

Removing soft DRM would rely on the non-anonymous person to do so, before handing the ebook on to someone else. Not doing so would have her/him run the risk of the passed on ebook being made even more public with name identification attached. I can only assume that for some of the potential passers-on, this is a deterrent.

You also would have to trust the software that removes the watermarking. Removing metadata is not enough, since the watermarking could be added via steganographic approach. Some formats such as PDF, have a plethora of possibilities to hide information. And you would have to remove images from an EPUB file, or severely change them, as there are watermarks for images that survive some of the re-renderings of the images. And your name could be watermarked in any or all of the images included in a book.

  • The draw backs you mention are almost the point of this type of system.
    – Chad
    Jan 2, 2014 at 2:53

For me, Soft DRM is a viable option that helps the book provider to identify who they provided the book for/to. I'm not aware of any formal analysis, or reports, of how Soft DRM fares in terms of things like unauthorized copying. I've found 'soft copies' of books online that were watermarked for someone else so unauthorized copies/distribution exists. However cracked (most likely unathorized) copies of 'hard' DRM books are also available on the internet.

In terms of my own purchasing practices, in 2013 I personally bought at least 50 ebooks online. These were mainly technical books. I bought the vast majority from 3 publishers: O'Reilly, Pragmatic Programmers, and Packt Publishing. They are all DRM Free. https://www.packtpub.com/about http://shop.oreilly.com/category/ebooks.do http://pragprog.com/frequently-asked-questions/ebooks (they say most, not all books are DRM free. The ones I've bought from them, at least 10 titles, all are).

I have bought various books that have soft DRM e.g. from Apress http://www.apress.com/customer-support/ and Commonsware https://wares.commonsware.com/

And I've bought very few books with active DRM, with one exception - ebooks bought for Kindles. I explain some of my reasons later on in this reply.

Here's my original answer, which includes some of my opinions (as requested by the question)

I am happy to buy ebooks with watermarks such as 'prepared for Julian Harty' as I'm able to easily copy the file onto the various computers and devices I use from time to time over the years. (I have ebooks first obtained over a decade ago, my computers from those days tend to have died.)

Having a watermark is a low-barrier for people determined to share / copy material regardless of copyright, however for me it's part of an honour-based system where I've legitimately obtained material where I shouldn't share it.

I tend not to buy hard-DRM'd ebooks; the one exception being books from Amazon's Kindle store. The Kindle ecosystem is compelling and one I've gotten used to. One key benefit is global 3G access to content at no extra charge from my 3G Kindles. I'm willing to tolerate DRM on the Kindles, and haven't had problems reading my Kindle content on lots of devices over the years I've been using them.

So for any publishers who read this answer, please realize you're less likely for me to buy from you. I've not bought tens of technical books when I discovered the site uses DRM. Instead I'll find similar books from stores that don't use hard DRM. I want to be able to easily migrate stuff I buy from device to device over the years.

  • 2
    I completely agree with the point of never buying books with hard DRM.
    – Anthon
    Jan 1, 2014 at 14:08
  • Sorry, I'm flagging for deletion. As Chad said, this is just a personal opinion, not backed up by any facts/research. Mind you, the question seems designed to solicit such.
    – DVK
    Jan 2, 2014 at 16:57
  • The facts are my behaviour; albeit a small sample size :) Jan 2, 2014 at 17:33
  • @Chad ad -at-DVK (I'm not allowed to include both of you in the same comment) thank you for your comments. I've revised my answer where I've tried to add some more data and evidence for the rest of my answer. I'd appreciate your suggestions on further ways to improve the answer to this question. Jan 3, 2014 at 22:33
  • @DVK Please see my comment and request for your suggestions above. I've had to write a separate comment to you to satisfy SE... Jan 3, 2014 at 22:34

There is a technology called digital fingerprinting. You can embed a GUID based signature into the metadata of the EBook that the Distributor can link to the original sale of the book. It is not an overt method of identification in that your personally identifiable information is not out there for anyone to find and potentially exploit. But if your e books show up on Torrent or for download on your sites, the companies could potentially use it to build a case of copyright infringement.

This technique is used in many DRM protected books as well as it is basically a fairly trivial effort for most people to find a tool to strip the DRM from a book. The finger print means that the DRM can be stripped but the original copy can be traced back to the original buyer.

That said the fingerprint is not by itself proof that you broke copyright. But if you are linked to it through other methods as well, it can help a prosecutor or an attorney for the rights holder to make a case of infringement.

  • Is there any evidence that digital fingerprinting is actually used in ebooks?
    – DVK
    Jan 2, 2014 at 4:38
  • @DVK - Is there a reason you have to be so contentious? Yes there are several vendors who are using the digital fingerprint.
    – Chad
    Jan 2, 2014 at 15:11
  • 1
    why is constructively suggesting a way to improve a question "contentious"? No need to get rude out of defensiveness - I was proposing how to make the answer better, not casting doubt. "Vendor XYZ does it" or "here's how book ABC has a watermark" is markedly better than mere "is used".
    – DVK
    Jan 2, 2014 at 15:38
  • @DVK - You could have suggested that directly instead of passive agressively. I will not point out what drm schemes use this. If some one else wants to that is their business.
    – Chad
    Jan 2, 2014 at 16:50

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.