How Can I Tell If An iBooks Book Is Copy-Protected (DRM)?
Yes, find the book in iTunes on your Mac and select it. Go to File > Get Info and click on the Summary tab. Next to the Kind label it will say either Book, Purchased Book, or Protected Book. Book and Purchased Book are both DRM-free (the latter being a DRM-free book from the iBookstore. Protected Book refers to a copy-protected book that was purchased from the iBookstore.