Apple, Amazon get patents to offer ‘used’ digital goods, article.
Wow, what can of worms is opened here? Amazon may have a de facto monopoly on the reselling of "used" digital goods? That sounds like a licence to tax the air. What a gig if you can get it.
Another worm is that presumably the author/copyright holder only gets paid the first time, while Amazon gets a bit of the pie every time a file is re-sold. Technically a similar thing is true for used physical items, but there, there's a natural friction from the physicality, and physical goods get worn, unlike digital ones. A digital file can get resold dozens of times, with Amazon getting a bite each time, and still be in pristine mint condition.