> As for selling a modified version, if it isn't modified enough than you still infringe copyright of the original author. With "enough" being something that needs to be defended in court if challenged.

Hang on. Does "modified version" mean the same physical copy I bought and then modified, or a copy I made myself and then modified?

The way you worded that sounds like you're talking about both, but the former makes no sense. Why would it be a copyright violation to buy a book, white-out one sentence, and resell it? And elsjaako was definitely talking about the former.

> Why would it be a copyright violation to buy a book, white-out one sentence, and resell it? //

Because of exhaustion of rights working on first sale of right to _make_ derivative copyright works not being exhausted on sale.

In USA under Fair Use you have pretty liberal rights compared to most other copyright regimes AFAICT. In the UK we don't have rights, not even under Fair Dealing, to modify works, never mind sell modified works (without permission of the copyright holder); they made an exception to allow caching to make web browsing lawful!

I can't buy your book, edit out part I don't like and resell it as your book, and I can't sell it as my book without your permission. Not even one copy. That's reasonable to me (unless there was a [implied] license for modifications to be made, say). I should of course be allowed to modify the physical copy I purchased as that's ordinary use and copyright shouldn't interfere with that.

Exactly, I meant modifying a physical copy (like a physical book from a shelf in a store), never actually copying anything in there.

I would be very interested to learn I was wrong about that.

You must be wrong, or literally every used textbook with notes in the margins is infringing on copyright. Although you could be correct, it’s just literally unenforceable.

That reminds me of the PureFlix case years ago. Their shtick was editing movies to be more "Christian-friendly". So what they did was heavily edit a movie and burn it to a disk and ship it to you. What they did was they also bought a legit copy of the movie on disk and damaged the disk to unusuable. They shipped you both, so you had a working edited disk and a broken original.

IIRC, they lost the case but I do see the merits in their arguments.

Can you have your kid or personal assistant do that for you?

Over-the-trope example: A wealthy old English aristocrat's head butler brings in his master's evening paper at the kitchen door. Then snips out any stories "which might disagree with master's digestion", before presenting the paper to the old blue blood.

What about if I bought a book from a bookstore then I wrote in the margins or highlighted some text and then sold it to used bookstore?

In my personal opinion the modification is insubstantial so for copyright purposes you haven't created a derivative work. There are probably ways you could make it substantial but how would the rights holders ever know. It might technically be a tort but there's no damage; what would a rights holder win?

> It might technically be a tort but there's no damage; what would a rights holder win?

Statutory damages.

Which highlights the essential flaw in allowing statutory damages.