There's a reason this as filed in the southern district of NY [1]. IA will lose based on the results of the Redigi case. The court found that in the case of a digital phonorecord that the "tangible medium" was the hard drive of the device it was downloaded to. Thus if you want to resell an MP3 you need to sell your hard drive. You can't just copy it to someone else's and then delete it. Any copy other than the original was found to be an illegal copy.
They never even looked at First Sale Doctrine which is a possible defense in this type of dispute.
If you translate this too books then the book itself is the tangible medium. Scans are infringing copies and only valid for personal use.
[1] https://en.wikipedia.org/wiki/Capitol_Records,_LLC_v._ReDigi...