The Verge has just reported that a new version of Requiem (v3.3), a Mac and Windows app that removes Fairplay digital rights management (DRM) from iTunes music and movies, now also removes DRM from iBooks ebooks.
As The Verge points out, while Apple had dropped FairPlay DRM for music in 2009, apps, movies and iBooks from iTunes still utilize some form of DRM copy protection.
It is the first time that iBooks DRM copy protection has been cracked. Removing DRM copy protections makes it possible to open and read iBooks ePub files on non-iOS devices.
The Verge confirms that they have used Requiem to remove the DRM from iBooks ePub files and were able to open and read them on multiple non-iOS devices.
Requiem was first released in February 2008 and since then Apple has been playing a cat and mouse game with developers of Requiem by releasing a new version of iTunes that disables Requiem. So expect Apple to release an update version of iTunes very soon.