Robert Aronoff

There is no such thing as a dog-eared e-book — each copy is forever perfect. But a new Amazon patent could go a long way toward making the digital media in our lives a lot more like the physical version.

Last week, Amazon patented a way to sell “used” e-books, music, videos, apps and other “digital objects.” The marketplace described in the patent would let such exchanges take place by cutting off the seller’s access to a piece of digital content once the buyer paid.