Common digital rights management systems for ebooks
Today, most popular ebooks are sold with DRM protection which is usually applied by retailers at the insistence of publishers and authors. There are several DRM systems in use. The most common systems used with ebooks are:
- Apple Fairplay DRM, used only with Apple’s products
- Amazon DRM, used only with Amazon products
- Adobe ADEPT DRM. Adobe sells its Adobe Content Server technology to anyone who wants it so, while the DRM technology is proprietary, its use is widespread and it has become the de facto industry standard. Adobe DRM is supported by several ebook and e-reader vendors including Kobo, Barnes and Noble, Google, Sony; OverDrive and Ingram (including library lending), Lulu (self-publishers) and — in e-reading apps — BlueFire, Txtr, Aldiko and Copia.
As well as restricting users from copying and distributing the entire ebook file, DRM can:
- Limit the number of devices a user can load their ebook onto (typically about six)
- Time-limit access, eg for library lending
- Restrict printing or copy-and-paste
- Provide a limited lending facility, eg to lend an ebook to a friend
DRM differences can prevent an ebook in the industry standard EPUB format from being transferred to another e-reader, even if it supports EPUB. Since most commercial ebooks are sold with DRM, users won’t be able to read them on other devices.
- Both Apple and Kobo support the EPUB format but they each use a different DRM system. So an ebook bought through Apple’s iBookstore can’t be read on a Kobo Ereader.
- Many e-readers support ebooks in Amazon’s mobi format. But when Amazon’s special DRM is applied, these ebooks can only be read on Amazon’s own devices and apps.
- You can read an EPUB file on any EPUB device if the ebook is unencrypted (that is, DRM-free).
- If they are Adobe DRM-encrypted EPUB files, only some EPUB devices and apps will let you read them. E-reader devices that support Adobe DRM include Kobo, Sony and Nook. E-reader apps that support Adobe DRM include Kobo, Nook, Google, OverDrive (libraries), Bluefire, and Readmill. The files can be read on any of these devices, though in practice it’s complex and beyond most consumers’ ability to move them between devices.
Confused? So are readers.
To DRM or not to DRM
DRM makes ebooks more complex to use and to sell, making it unpopular with consumers and limiting publishers’ options to sell ebooks.
But behind its use is the legitimate concern of many publishers and authors that books could follow the fate of music and other digital media in suffering from widespread piracy. DRM also allows libraries to lend ebooks by managing the loan expiry.
For each of your titles, you’ll have to decide whether to use DRM. As well as giving (some) protection against copying, DRM will affect where your ebooks can be sold. DRM is usually applied by the retailer and requires complex and expensive technology. This makes it difficult if you want to sell your ebooks through smaller players such as local booksellers, bloggers or, indeed, your own website.
But DRM can be implemented in a way that makes it simple for the user. A good example of this is Amazon’s system, which is so well integrated into the user’s overall experience that most users are probably unaware of it. Another example is watermarking and so-called ‘social DRM’.
Watermarking and ‘social DRM’
The most commonly-used DRM systems encrypt ebooks with special codes, making it difficult or impossible to open a file unless you have the key and appropriate software to unencrypt it. This makes it difficult to use. An alternative is digital watermarking which eases the issues associated with reading, distribution and preservation.
Watermarking embeds visible and invisible text and images into the ebook file, allowing it to be freely copied and used like a DRM-free file. It is also referred to as social DRM because most systems embed information about the purchaser, such as customer or credit card number, to make the file traceable and discourage sharing.
Older formats like Microsoft’s .LIT format and Barnes and Noble’s Ereader have used watermarking but it gained renewed attention when Pottermore, the website set up by Harry Potter author J K Rowling, adopted social DRM from a company called BooXtream to sell Harry Potter ebooks.
Find out more about this topic on our Digital Publishing 101 useful resources site.