If you don’t want to use calibre, for whatever reason, here is an alternative.
The simplest way to remove the DRM from your ebooks is to use calibre and the DeDRM calibre plugin, as described in my post DeDRM plugin for calibre: the simplest option for removing DRM from most ebooks. Post updated on 22nd March, 2013 System Requirements: Mac OS X 10.4 and above.
